what must the charge (sign and magnitude) of a particle of mass 1.45 g be for it to remain stationary when placed in a downward-directed electric field of magnitude 700 n/c ?

The primary source of energy for most terrestrial ecosystems is the sun.

This is because the sun provides energy in the form of sunlight, which is used by plants and other autotrophs to carry out photosynthesis. During photosynthesis, plants convert sunlight into chemical energy in the form of glucose, which is used as a source of energy for the plant's growth and metabolism.

Other organisms in the ecosystem, such as herbivores and carnivores, rely on plants for their energy needs. Herbivores consume plant material, while carnivores consume other animals. In both cases, the energy that these organisms obtain ultimately comes from the sun, as it is the energy source that powers the plant growth and photosynthesis.

There are some exceptions to this general pattern, such as deep-sea ecosystems that rely on chemosynthesis instead of photosynthesis. However, in most terrestrial ecosystems, the sun is the primary source of energy that supports the growth and survival of the ecosystem's organisms.

In summary, the sun is the primary source of energy for most terrestrial ecosystems, providing the energy needed for plant growth and photosynthesis, which in turn supports the growth and survival of other organisms in the ecosystem.

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Momentum is not always conserved in real-life situations because external forces can act on a system and change its momentum.

For example, when two cars collide, friction and air resistance can cause the momentum of the system to change. Similarly, when a ball is thrown in the air, gravity and air resistance act on it and cause its momentum to change. Other factors such as deformation, energy loss, and imperfect collisions can also cause momentum to be lost or gained. Therefore, while momentum is a useful concept in physics, it is important to consider the impact of external factors when analyzing real-world situations.

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The net work on the ball if its velocity changes to (8i 4.00j)m/s is 27.60 Joules.

Using the work-energy principle, we know that the net work done on the ball is equal to the change in its kinetic energy.

To find the change in kinetic energy, we need to calculate the ball's final velocity and its initial velocity, and then use the formula:

Change in Kinetic Energy = (1/2) x mass x (final velocity)² - (1/2) x mass x (initial velocity)²

The net work done on the ball is 27.60 Joules.

So, when the ball changes its velocity from (6.60i-2.40j) m/s to (8i+4.00j) m/s, the net work done on it is 27.60 Joules.

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The current in the solenoid becomes 3.56 A.

How to find current in the solenoid?

Number of turns in the solenoid, n = 100 turns/cm

Radius of the circular path of electron, r = 2.30 cm

Speed of electron, v = 0.0460c, where c is the speed of light

To find: Current in the solenoid, i

Formula used: Magnetic field inside the solenoid,

B = μ0ni Where, μ0 = 4π × 10⁻⁷ T m/A is the permeability of free spaceSolution:

The force on a moving electron in a magnetic field is given by

F = Bev

Where B is the magnetic field, e is the charge of an electron and v is its velocity.

The force acting on the electron provides the necessary centripetal force for the electron to move in a circle of radius r.

So,

Bev = (mev²)/r

where me is the mass of an electron

On simplifying the above equation, we get

Be = (mev)/r

Put the value of B from the formula of magnetic field inside the solenoid, B = μ0ni

we get

μ0ni = (mev)/r

Solve for i,

i = (mev)/(μ0nr)

Substitute the given values and solve

i = (9.109 × 10⁻³¹ kg × 0.0460c × 3 × 10⁸ m/s)/(4π × 10⁻⁷ T m/A × 100 turns/cm × 2.30 cm)i

= 3.56 A

Therefore, the current in the solenoid is 3.56 A.

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The Maxwell equation ∇ × E = -∂B/∂t can be used to predict the magnetic field in a region of space in which the electric flux is changing.

The Maxwell equation ∇ × E = -∂B/∂t is one of the four Maxwell equations that describe the behavior of electric and magnetic fields. It relates the curl of the electric field to the time rate of change of the magnetic field. In other words, it describes how a changing electric field creates a magnetic field.

This equation is important in the study of electromagnetic waves, which are generated by changing electric and magnetic fields. When an electric field changes in time, it creates a magnetic field, which then creates an electric field, and so on, creating a self-sustaining wave.

The equation can be used to predict the behavior of electromagnetic waves in space, as well as the behavior of electric and magnetic fields in the presence of each other.

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Through the coil, the magnetic flux rises. The coil will experience a voltage as a result. This voltage will cause a current to flow. The amount of the emf increases with speed and is 0 in the absence of motion.

A current will be induced in a coil of wire if it is exposed to a shifting magnetic field. Because of an electric field that is being generated, which drives the charges to move around the wire, current is flowing.

Self-Inductance: When current passes through a coil, a magnetic field and consequent magnetic flux are created.

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The point at which the kinetic energy is lowest is 3 in the syringe containing an incompressible fluid that is vertically oriented and the plunger is slowly depressed.

The kinetic energy of an object is the energy it has due to its motion. When an object is in motion, it has kinetic energy. It is a scalar quantity that is proportional to the mass of the object and the square of its velocity. The formula for kinetic energy is given as follows:

                                KE = 1/2mv²

Where m is the mass of the object and v is its velocity.

Points 1 and 2 have higher kinetic energy because the incompressible fluid is still being compressed in the syringe. Point D is incorrect because the kinetic energy of the incompressible fluid is not the same at all three points. Point E is incorrect because enough information has been provided. Therefore, when a syringe containing an incompressible fluid is vertically oriented and the plunger is slowly depressed, the kinetic energy is lowest at point 3.

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According to the information, the speed increases up to 2,900 kilometers deep and then drops because the pressure is higher.

According to the information of the points we can infer that the speed gradually increases up to 2900 km depth. Once it exceeds this depth, it falls radically to 8.5 km/s (a little higher than the initial speed).

Its speed decreases radically because it exceeds the depth of 2900 km where the pressure is greatest.

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The magnitude of the force that the child exerts on the seat at the lowest point if his mass is 18.5 kg is 981 N.

To determine the magnitude of the force on the child, we must find the magnitude of the centripetal acceleration of the child at the low point first. We can use the equation:

[tex]a_{c}[/tex] = [tex]\frac{v^{2} }{r}[/tex]

where v = 9 m/s and r = 2 m

thus,

[tex]a_{c}[/tex] = [tex]\frac{9^{2} }{2}[/tex]

[tex]a_{c}[/tex] = 40.5 m/s²

And then, we find out the magnitude of the force that the child exerts on the seat at the lowest point if his mass is 18.5 kg.

∑[tex]f_{y}[/tex] = m × [tex]a_{c}[/tex]

[tex]f_{n}[/tex] - w = m × [tex]a_{c}[/tex]

[tex]f_{n}[/tex] = m × [tex]a_{c}[/tex] + w

[tex]f_{n}[/tex] = (18.5 × 40.5) + 18.5 (9.80)

[tex]f_{n}[/tex] = 981 N

Thus, the magnitude of the force that the child exerts on the seat at the lowest point if his mass is 18.5 kg in N is 981 N.

Your question is incomplete, but most probably your full question was

A mother pushes her child on a swing so that his speed is 9.00 m/s at the lowest point of his path. The swing is suspended 2.00 m above the child’s center of mass.

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The amount of work done is equal to 120 ft-lbs.

In the given scenario, we have a rope with a mass of 15 pounds hanging off the edge of a building. We need to lift the top 8 feet of the rope to the top of the building, and we want to calculate the work done in the process.

As we calculated previously, the weight of the rope is 147 pounds (15 pounds multiplied by the acceleration due to gravity, which is approximately 9.8 ft/s^2).

The distance over which the force is applied is 8 feet, as we need to lift the top 8 feet of the rope to the top of the building.

Using the formula for work:

Work = Force × Distance × Cosine of angle between Force and Displacement

we can plug in the values we have:

Work = 147 pounds × 8 feet × Cosine of angle between Force and Displacement

Now, since we are lifting the rope vertically upwards, the force and the displacement are in the same direction, which means the angle between them is 0 degrees. The cosine of 0 degrees is 1, so we can simplify the equation:

Work = 147 pounds × 8 feet × 1

Work = 1176 foot-pounds

So, the amount of work done to lift the top 8 feet of the rope to the top of the building is 1176 foot-pounds, not 120 foot-pounds as previously stated.

It's important to ensure that all the values, units, and calculations are accurate when calculating work, as it is a fundamental concept in physics and has practical applications in various fields, including engineering, mechanics, and energy calculations.

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Answer :Gravity is the force that attracts two objects towards each other; when an object falls under the influence of gravity alone, it is said to be in free fall and will accelerate at a constant rate; as the velocity of a falling object increases, air resistance will begin to slow it down until it reaches terminal velocity; when an object is thrown or launched, it follows a curved path known as projectile motion which is influenced by both gravity and air resistance.

The electric heater operates on 220 V and has a current of 12.8 A flowing through it. Ohm's law is used to find the resistance of the electric heater. The heater's resistance is 17.19 Ω.

Ohm's law states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points. It can be mathematically represented as:

V = IR

Where, V is the voltage across the two points,

I is the current flowing through the conductor, and

R is the resistance of the conductor.

Rearranging the equation to solve for the resistance:

R = V/I

The voltage across the electric heater is 220 V, and the current flowing through it is 12.8 A.

Therefore, the resistance of the electric heater can be calculated as follows:

R = 220/12.8R = 17.19 Ω

Thus, the heater's resistance is 17.19 Ω.

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The distance that a package will travel horizontally during its descent when a plane is flying at 800 miles per hour can be calculated using the following steps is 1600 miles.

Determine the time taken for the package to hit the ground. We know that when an object is dropped from a certain height, it falls under the influence of gravity.

The acceleration due to gravity is 9.8 m/s². The formula for the time taken for an object to fall can be given by:

t = √(2h/g)

where, t is the time taken for the object to fall is the height from which the object was dropped g is the acceleration due to gravity.

We know that the distance traveled by the package horizontally can be given by d = vt

where, d is the distance traveled horizontally by the package v is the velocity of the planet is the time taken for the package to hit the ground.

Thus, the distance is 1600 miles.

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The tension, p, in the cable needed to give the 105-lb block a steady acceleration of 7 ft/sec2 up the incline is 164.375 lbs.

To solve this, use the equation for acceleration due to gravity:
a = g*sin(theta) - (T/m)
Where:
a = the steady acceleration of 7 ft/sec2
g = acceleration due to gravity (32.2 ft/sec2)
theta = the incline angle
T = the tension in the cable
m = the mass of the block (105 lbs)
Solving for T yields:
T = m*(a + g*sin(theta))
Inserting the given values yields:
T = 105 lbs * (7 ft/sec2 + 32.2 ft/sec2*sin(theta))
T = 164.375 lbs

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F1 will be in the direction of negative x-axis)F2 = kQ2q/(0.013 - x)² (as Q2 is negative, therefore F2 will be in the direction of positive x-axis)As F1 = F2, we can equate both equations,kQ1q/x² = kQ2q/(0.013 - x)². For an electron, the charge is negative, It will experience force in the direction of the positive x-axis. Therefore, the net force will not be zero if an electron is placed at x = 8.7 mm.

Given that A 2.4 n C charge is at the origin and a -4.0 n C charge is at 1.3 cm. At what x-coordinate could you place a proton so that it would experience no net force? Would the net force be zero for an electron placed at the same position? The given charges are,Q1 = 2.4 n C (positive charge) placed at the origin.Q2 = -4.0 nC (negative charge) placed at 1.3 cm (this can be converted to meters, which is 0.013m).Let's assume that a proton is placed at x distance from the origin at which it experiences no net force. If F1 is the force due to Q1 and F2 is the force due to Q2 then the net force on the proton will be, F net = F1 + F2

As we know that F1 and F2 are in opposite directions, the net force will be zero, therefore,F1 = F2If we apply Coulomb's law, then; F1 = kQ1q/x² (as both charges are positive, therefore F1 will be in the direction of negative x-axis)F2 = kQ2q/(0.013 - x)² (as Q2 is negative, therefore F2 will be in the direction of positive x-axis)As F1 = F2, we can equate both equations,kQ1q/x² = kQ2q/(0.013 - x)²Solving this equation for x, we get, x = 0.0087 m or 8.7 mm (approximately)Therefore, if a proton is placed at x = 8.7 mm, it will experience no net force. Would the net force be zero for an electron placed at the same position? For an electron, the charge is negative, therefore it will experience force in the direction of the positive x-axis. Therefore, the net force will not be zero if an electron is placed at x = 8.7 mm.

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The reading on the scale is 838.29 N.

To determine the reading on the scale, use the following formula:

F = ma

where F is force, m is mass, and a is acceleration.

The weight of the individual can be determined using the formula:

W = mg

where W is weight, m is mass, and g is the acceleration due to gravity, which is 9.81 m/s².

The given acceleration is 0.47 m/s². The weight of the individual is W = mg,

where m = 799 N / 9.81 m/s² = 81.38 kg

W = 81.38 kg x 9.81 m/s² = 798.11 N.

To calculate the reading on the scale, we'll have to add the force the scale must apply to support the individual's weight to the weight of the person's mass multiplied by the acceleration:

Reading on the scale = 798.11 N + 81.38 kg x 0.47 m/s² = 838.29 N, rounded to three digits.

Therefore, the reading on the scale is 838.29 N to at least three digits.

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The number of electrons per second striking the target is 0.00055 x 6.24 x 1018 = 3.44 x 10^15 electrons per second.

To calculate the number of electrons per second that strike a target when the electric current is 0.55 mA, we can use the equation: I = Q/t Where I is the electric current, Q is the charge, and t is the time. We can rearrange this equation to find Q as: Q = I

The charge of an electron is -1.6 x 10^-19 C. So, we can find the number of electrons that pass through a point by dividing the charge by the charge of one electron: n = Q/e Where n is the number of electrons and e is the charge of one electron. Substituting our values:n = 0.00055 / -1.6 x 10^-19n = -3.44 x 10^15.

This gives us a negative number, which means that the electrons are moving in the opposite direction to the conventional current. To find the absolute value of the number of electrons: n = 3.44 x 10^15.

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When the circuit is closed, the direction of the force exerted on the wire by the magnet is to the left.

A magnet placed near a wire creates a magnetic field. A wire carrying a current produces a magnetic field around it. These two fields interact, resulting in a force on the wire that is perpendicular to both the magnetic field of the magnet and the current in the wire. When the circuit is closed, a current is flowing through the wire. The current direction is shown in the picture below.

When a current-carrying wire is placed in a magnetic field, a force is exerted on the wire. The force is perpendicular to both the direction of the magnetic field and the direction of the current in the wire. The force is proportional to the strength of the magnetic field, the current in the wire, and the length of the wire within the magnetic field.

When the current flows, a magnetic field is produced around the wire that points upwards, as shown by the green arrows. When the magnetic field of the magnet is also taken into account, the direction of the force exerted on the wire is to the left, as shown by the blue arrow. Therefore, the answer is that when the circuit is closed, the direction of the force exerted on the wire by the magnet is to the left.

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If the hole is 5.6 m from a 1.9- m -tall person then, the image of the person on the film will be: 0.63m tall

The image height of the person on the film can be determined by using the magnification formula. The magnification formula is given as: m=-i/o Where m is the magnification of the image, i is the height of the image, and o is the distance of the object from the lens.

Now, the height of the person is 1.9m and the distance of the hole from the person is 5.6m, so we can determine the distance of the object from the lens, which is given as:o=5.6+1.9o=7.5m. Since the distance of the object from the lens has been determined, the magnification of the image can now be determined.

Using the magnification formula: m=-i/o Where i is the height of the image and o is the distance of the object from the lens. [tex]m=-i/o=-(1.9m)/7.5m= -0.2533[/tex]

We can now use the magnification formula to determine the height of the image. Rearranging the formula: [tex]i=m*o= (-0.2533) * 7.5mi=-1.9m * 0.2533i=-0.63m[/tex]

Therefore, the image height of the person on the film is 0.63m.

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The primary mirror of an astronomical telescope is often shaped and polished to a parabolic shape because a parabolic shape allows for the mirror to collect the most amount of light and focus the parallel rays of light to a single point for better image clarity.

The reason that the primary mirror of an astronomical telescope is often shaped and polished to a parabolic shape is to reduce spherical aberration.

What is an astronomical telescope?An astronomical telescope is an optical instrument that aids in the observation of remote objects by collecting electromagnetic radiation such as visible light. It consists of two primary components: a primary mirror or lens that gathers and focuses light, and an eyepiece or camera that magnifies and projects the image formed by the primary.

A parabolic shape is a mirror or lens that has a curve that is more curved in the center than at the edges, and it is often used in astronomical telescopes to reduce spherical aberration. Spherical aberration is an optical defect that causes the image of a point source to become fuzzy and blurred. It occurs when the rays passing through the edges of a spherical lens or mirror become focused at a different distance than those passing through the center. This causes the image to be blurred around the edges, which makes it difficult to view small or distant objects. Parabolic mirrors are used to correct this problem because they are designed to focus all incoming light to a single point, resulting in a sharper and clearer image.

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The waves will cancel each other out and no waves will remain. If two waves of the same frequency, but different amplitudes, interfere with each other, the resulting wave will have an amplitude equal to the sum of the two wave amplitudes.

Pulse waves are pressure waves that are created as the heart pumps blood throughout the body. They are detected through pulse points, such as on the wrists, neck, or temples. Pulse waves can be measured using a device called a pulse oximeter, which uses a sensor to detect the pressure of the pulse wave.

Pulse waves can provide information about a person’s heart rate and oxygen saturation levels.

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Explanation:

The option that best describes the image when an object is placed at a distance greater than twice the focal length in front of a concave mirror is:

"An inverted image which is smaller than the object and located between the focal point and the center of curvature of the mirror.

"When an object is placed at a distance greater than twice the focal length in front of a concave mirror, a virtual, upright, and magnified image is formed.

As per the rules of concave mirrors, when an object is placed beyond the center of curvature, an inverted and real image is produced.

As a result, option (A) is incorrect.

When the object is placed at the center of curvature, the size of the image is equal to that of the object, and it is inverted.

As a result, option (C) is incorrect.

When an object is placed at a distance that is less than twice the focal length, the image formed is virtual, erect, and magnified.

As a result, option (D) is incorrect.

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The moment of inertia of the wheel is gotten to be I = 41.2 kg.m²

Angular displacement = 5.55 revolutions × 2π radians/revolution

Angular displacement = 34.9 radians

Angular acceleration:

Angular acceleration = (final angular velocity - initial angular velocity) / time

Angular acceleration = (88.8 rad/sec - 0 rad/sec) / 0 s

Angular acceleration = 88.8 rad/sec²

Moment of inertia.

Moment of inertia = (torque × angular displacement) / angular acceleration

Moment of inertia = (77.7 Nm × 34.9 radians) / 88.8 rad/sec²

Moment of inertia = 41.2 kg.m²

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A basketball whose mass is 0.540 kg falls from rest through a height of 5.65 m and then bounces back. on its way up it, passes by a height of 3.25 m with a speed of 2.35 m/s. The energy lost during the bounce is: 28.67 Joules

When a basketball is dropped from rest through a certain height and rebounds, it loses energy due to friction, deformation, and air resistance. In this situation, a basketball falls from rest from a height of 5.65 meters and rebounds, passing a height of 3.25 meters with a speed of 2.35 meters per second.

We know that work done W = mgh,

where, m = mass of the ball g = acceleration due to gravity h = height of the ball.

Energy lost during the bounce can be calculated by subtracting the kinetic energy of the ball after the bounce from its initial potential energy. When a ball falls from a certain height, it has initial potential energy due to its position in the earth's gravitational field.

When the ball rebounds, it has a certain kinetic energy that can be calculated using the conservation of energy equation. Therefore, the difference between the ball's initial potential energy and its rebound kinetic energy is the energy lost during the bounce.

Conservation of energy is applicable in this situation because the total energy before and after the bounce must remain constant if no external work is done on the ball. Therefore, we can apply the law of conservation of energy to this situation. The Kinetic Energy of the ball after rebounding can be calculated as:

K.E. = 1/2 mv²

Where, m = mass of the ball, v = velocity of the ball

The potential energy of the ball before rebounding can be calculated as: P.E. = mgh, Where, m = mass of the ball, g = acceleration due to gravity, h = height of the ball

Therefore, the initial potential energy of the ball can be calculated as: [tex]P.E. = 0.540 kg x 9.8 m/s² x 5.65 mP.E. = 30.2 Joules[/tex]

The ball rebounds and reaches a height of 3.25 m with a speed of 2.35 m/s.

Kinetic Energy of the ball after rebounding can be calculated as:

K.E. = 1/2 mv²

K.E. = 0.5 x 0.540 kg x (2.35 m/s)²

K.E. = 1.53 Joules.

Energy lost during the bounce = Initial Potential Energy - Rebound Kinetic Energy.

Energy lost during the bounce = 30.2 J - 1.53 J

Energy lost during the bounce = 28.67 J

Therefore, the energy lost during the bounce is 28.67 Joules.

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To change 500g of water at room temperature (20°C) to steam at 100°C, you will need to add 1128.500 kJ of heat. This is because water requires a certain amount of heat energy, called the 'latent heat of vaporization', to turn from a liquid to a gas.

Mass of water (m) = 500g

Initial temperature ([tex]T_i[/tex]) = 20°C

Final temperature ([tex]T_f[/tex]) = 100°C

The heat of vaporization ([tex]H_{vap}[/tex]) = 2260 J/g.

To calculate the amount of heat required to convert 500 g of water at room temperature to steam at 100°C, we will use the formula:

[tex]Q = m \times H_{vap}\\Q = 500 g \times 2260 J/g\\Q = 1128500 J[/tex]

Therefore, it would take 1130000 J of heat to change this water to steam at 100°C.

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The image size on the retina of a person of height 1.8 m standing 8.0 m away is: 0.094 cm.

The size of the image on the retina of a person of height 1.8 m standing 8.0 m away is determined by the size of the object, the distance between the object and the lens, and the distance between the lens and the retina.

The image size on the retina is inversely proportional to the distance between the object and the lens and is directly proportional to the distance between the lens and the retina. In this case, the object is 1.8 m away and the lens is 1.7 cm from the retina.

Therefore, the image size on the retina is (1.7 cm/1.8 m) times 8.0 m, or 0.094 cm. This means that the image size on the retina of a person of height 1.8 m standing 8.0 m away is 0.094 cm.

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Answer:

Whether the object or fluid is moving, drag occurs as long as there is a difference in their velocities. Because it is resistant to motion, drag tends to slow down the object. An effective way to reduce it is to alter the shape of the object and make it streamline. Drag Force Examples of Drag Force

Explanation:

To determine the angular acceleration of the 4-kg slender bar released from rest in the position shown, we need to consider two cases:

(a) when the surface is rough and the bar does not slip, and

(b) when the surface is smooth.

(a) Rough surface (no slip):
1. Calculate the torque about the center of mass (CM). In this case, the only force causing the torque is gravity (mg), acting downward at the midpoint of the bar.
2. Calculate the moment of inertia (I) for the bar. Since it's a slender bar, I = (1/12) * mass * length^2.
3. Use Newton's second law for rotation:

Torque = I * angular acceleration (α). Solve for α.

(b) Smooth surface:
1. Calculate the torque about the point of contact (A) with the surface. In this case, the gravitational force (mg) acts downward at the midpoint of the bar and the frictional force (f) acts upward at point A.
2. Calculate the moment of inertia (I) for the bar about point A. Use the parallel axis theorem: I_A = I_CM + mass * distance^2.
3. Use Newton's second law for rotation:

Torque = I_A * angular acceleration (α). Solve for α.

By following these steps, you will be able to determine the angular acceleration of the 4-kg slender bar in both cases, when the surface is rough and when the surface is smooth.

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Answer:

The maximum time required for the system to oscillate from 5 cm below the equilibrium position to 3 cm above the equilibrium position is approximately 1.309 seconds.

Explanation:

The time period (T) of a mass-spring system is given by:

T = 2π√(m/k)

where m is the mass attached to the spring, and k is the spring constant.

Given that the spring is displaced 5 cm below its equilibrium position and travels from the lowest point to the highest point within 0.25 sec. This means that the time period of the system is:

T = 2(0.25) = 0.5 sec

Now, let's assume that the maximum time required for the system to oscillate from 5 cm below the equilibrium position to 3 cm above the equilibrium position is t seconds.

So, the time taken for the system to move from the lowest point to 3 cm above the equilibrium position is (t/2) seconds.

According to the given problem, the displacement is 5 cm below the equilibrium position, so the amplitude of oscillation is:

A = (5 + 3) / 2 = 4 cm

Now, using the formula for time period, we get:

T = 2π√(m/k) ---- (1)

We know that the maximum displacement (amplitude) of oscillation, A = 4 cm. This can be expressed in terms of mass and spring constant as:

A = (m * g) / k ---- (2)

where g is the acceleration due to gravity.

Squaring equation (2) and solving for m/k, we get:

(m/k) = (A * k) / g)^2 ---- (3)

Substituting equation (3) into equation (1), we get:

T = 2π√[((A * k) / g)^2] ---- (4)

Simplifying equation (4), we get:

T = 2π * (A / g) * √(1/k) ---- (5)

Now, substituting the values of T, A, and g into equation (5), we get:

0.5 = 2π * (4 / 9.8) * √(1/k)

Simplifying this equation, we get:

√(k) = 2π * (4 / 9.8) / 0.5

√(k) = 10.239

k = 105

So, the spring constant is 105 N/m.

Now, substituting the value of k into equation (3), we get:

(m/k) = (A * k / g)^2

(m/k) = (4 * 105 / 9.8)^2

(m/k) = 73.88

So, the mass attached to the spring is:

m = (73.88) * (105)

m = 7757.4 g

m = 7.7574 kg

Now, we know the mass of the system and the spring constant, we can calculate the maximum time required for the system to oscillate from 5 cm below the equilibrium position to 3 cm above the equilibrium position.

The time period (T) of the system is given by:

T = 2π√(m/k)

T = 2π√(7.7574/105)

T = 1.309 sec (approx)

Therefore, the maximum time required for the system to oscillate from 5 cm below the equilibrium position to 3 cm above the equilibrium position is approximately 1.309 seconds.

A dieter lifting a 10 kg mass 1000 times to a height of 0.5m each time does 49.05 J of work per lift, resulting in the total amount of work done and fat burned is calculated by total amount of energy.

(a) The amount of work done against the gravitational force is calculated by using the formula:

W = m*g*h

where m is the mass,

g is the acceleration due to gravity, and

h is the height.

The person lifts a 10 kg mass to a height of 0.5 meters, so the work done each time is:

[tex]W = (10 kg) * (9.8 m/s^2) * (0.5 m) = 49 Joules.[/tex]

The total work done against the gravitational force is:

[tex]W_{total}= (49 J) * (1000) = 49,000 J.[/tex]

(b) To calculate the amount of fat burned, we need to find the total amount of energy expended and divide it by the efficiency rate and the energy per kilogram of fat.

The total amount of energy expended by the person is:

[tex]E_{total} = W_{total} = 49,000 J.[/tex]

The efficiency rate is 20%, which means that 20% of the expended energy is converted to mechanical energy.

The energy per kilogram of fat is [tex]3.8*10^7[/tex] Joules/kg.

Therefore, the amount of fat burned is:

Fat burned = [tex]E_{total}[/tex] / (efficiency rate * energy per kg of fat)

Fat burned = 49,000 J / (0.2 * 3.8 x 10⁷ J/kg)

Fat burned = 0.0645 kg of fat (or 64.5 grams of fat).

So, the person will burn approximately 64.5 grams of fat by lifting a 10 kg mass 1000 times to a height of 0.5 meters each time.

Also the total work done against gravitational force is 49,000J.

To Practice for 'mechanical energy':

https://brainly.com/question/29803154

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