Lenny wrote the steps he used to find the mass of an object with 400 J of energy moving at a velocity of 8 m/s.
1. Find the square of 8 m/s, which is 64 m2/s2.
2. Divide kinetic energy, 400 J, by 64 m2/s2, which is 6.25 J per m2/s2.
3. Divide 6.25 J per m2/s2 by 2 to get a mass of 3.125 kg.

Which best describes Lenny’s error?

A. In Step 1, he should have found the square root of 400 J instead of squaring 8 m/s.
B. In Step 1, he should have multiplied 8 m/s by 2 instead of squaring it.
C. In Step 2, he should have divided 64 m2/s2 by 400 J instead of dividing 400 J by 64 D. m2/s2.
In Step 3, he should have multiplied 6.25 J per m2/s2 by 2 instead of dividing it by 2.

Answer:

250 N

Explanation:

F=ma

F=50 kg(5 m/s/s)

F=250 N

Answer:

F=250N

Explanation:

I hope this helps you out and if your feeling generous plz mark brainliest it helps me a lot thank you:)

Answer:

4.5 m/s

Explanation:

[tex]s_x[/tex] = Horizontal displacement = 1.8 m

[tex]s_y[/tex] = Vertical displacement = 0.8 m

[tex]u_x[/tex] = Horizontal velocity

g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]

t = Time taken to fall down

[tex]s_y=u_yt+\dfrac{1}{2}gt^2\\\Rightarrow 0.8=0+\dfrac{1}{2}\times 9.8\times t^2\\\Rightarrow t=\sqrt{\dfrac{2\times 0.8}{9.8}}\\\Rightarrow t=0.4\ \text{s}[/tex]

[tex]s_x=u_xt+\dfrac{1}{2}a_xt^2\\\Rightarrow 1.8=u_x\times 0.4+0\\\Rightarrow u_x=\dfrac{1.8}{0.4}\\\Rightarrow u_x=4.5\ \text{m/s}[/tex]

The initial velocity of the marble is 4.5 m/s.

Answer:13.9 on edgy I just did it

Explanation:

Answer:

13.9

Explanation:

just did it

Answer:

the lion will miss the zebra by 3 meters

Explanation

The zebra has gone 23.75m after 5 seconds

and the lion can only go 20 m/s

The lion can not catch zebra.

A diagram is attached below which describe situation of question.

The speed of Zebra is,

      [tex]v=u+at=0+4t=4t[/tex]

Where u is initial speed of zebra.

The speed of lion is 20m/s.

The lead in speed by lion for every second is [tex](20-4t)[/tex].

             [tex](20-4t)*t=60\\\\20t-4t^{2}=60\\ \\t^{2}-5t+15=0\\ \\t=\frac{5\pm\sqrt{(-35)} }{2}[/tex]

Here time is imaginary.

Therefore, The lion can not catch zebra.

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Answer:

mass

.

Explanation:

Answer:

It would be B

Explanation:

Let w denote the weight of the box, n the magnitude of the normal force (the sheet pushing up on the box), k the magnitude of the kinetic friction force, and µ the coefficient of kinetic friction.

The kinetic friction force doesn't kick in until the sheet is tilted at an angle θ₂. Since the box is sliding down at constant speed, it's in equilibrium and the forces acting on it sum to 0.

In the horizontal direction (literally left-and-right, parallel to the ground and not the sheet), we have only the horizontal components of the friction and normal forces to worry about, so that [tex]\mathbf n_x+\mathbf f_x=\mathbf0[/tex], which reduces to

f cos(θ₂) + n cos(90º + θ₂) = 0

(where we take the right to be positive and left to be negative)

Recall that cos(90º + x) = -sin(x) for all x, and that the friction force is proportional to the normal force by a factor of µ. This gives

µ n cos(θ₂) - n sin(θ₂) = 0

Solve for µ :

µ n cos(θ₂) = n sin(θ₂)

µ = sin(θ₂) / cos(θ₂)

µ = tan(θ₂)

Answer:

sorry im not in physics

Explanation:

Answer:

lm.ao i was stuck too when i was on that

Explanation:

what u need to know sis?

speed, being a scalar quantity, is the rate at which an object covers distance. The average speed is the distance (a scalar quantity) per time ratio. Speed is ignorant of direction. On the other hand, velocity is a vector quantity; it is direction-aware. Velocity is the rate at which the position changes.

Answer:

this density is in the range of Peridotite type rocks

Explanation:

In this graduated cylinder exercise we can directly read the volume of the rock

         V = (35 - 30) cm³

          V = 5 cm³

They also indicate the mass of the rock

          m = 15.5 gr.

Density is defined as the ratio of mass to volume

          ρ = 15.5 / 5

          ρ= 3.1  gr /cm³

When checking the attached table this density is in the range of Peridotite type rocks

The type of rock the students mostly like have is Peridotite.

We'll begin by calculating the volume of the rock. This can be obtained as follow:

Volume of water = 30 mL

Volume of water + rock = 35 mL

Volume of rock = (Volume of water + rock) – (Volume of water)

Volume of rock = 35 – 30

Volume of rock = 5 mL = 5 cm³

Mass of rock = 15.5 g

Density = mass / volume

Density of rock = 15.5 / 5

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Answer:

9.8m/s

Explanation:

Given,

distance of each storey () = 4.9m

distance of 4 storey (s) = 19.6m

acceleration due to gravity (g) = 9.8 m/s^2

time given (t) = ?

velocity = (?)

initial velocity (u) = 0 {due to fall from certain height}

using formula,

s = ut + 1÷2at^2

s = 0 + 9.8÷2×t^2

19.6×2÷9.8 = t^2

4 = t^2

t = 2

now,

velocity ( v )= s ÷ t

v = 19.6 ÷ 2

v = 9.8 m/s

ans

Displacement and velocity are the two quantities that can be used to describe motion.

Motion is defined in terms of displacement, time, velocity, and acceleration. Velocity is defined as the rate of change of displacement whereas acceleration is defined as the rate of change of velocity.

Most of the quantities used to describe motion can be categorized as vectors or scalars. A vector is a quantity that is described by both magnitude and direction whereas a scalar is a quantity that is described by magnitude only.

The motion of an object can be defined as Uniform motion which means equal distance is covered in equal time and a non-uniform motion means an equal distance is covered by an object in equal intervals of time.

So we can conclude that option A is the correct answer.

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Answer:

p=-540kg•m/s

Explanation:

because I used a calc

Answer:

Kelvin

Explanation:

Kelvin is the universal and scientific unit for temperature as Celsius and Fahrenheit temperatures we use in everyday situations

Answer:

0.25

Explanation:

Answer:

Since the KE is proportional to velocity squared, if you increase the KE by a factor of

2

, you increase

v

by a factor of

2

2

=

4

Detailed explanation :

25

=

0.5

⋅

m

⋅

(

5

2

)

Find

m

:

25

=

25

m

2

m

=

2

Hence the new KE:

KE

=

0.5

⋅

2

⋅

10

2

KE

=

100

J

Explanation:

Vector, in physics, a quantity that has both magnitude and direction. It is typically represented by an arrow whose direction is the same as that of the quantity and whose length is proportional to the quantity's magnitude.

Answer:

0.33 seconds

Explanation:

The time taken by the apple to reach the ground will be 0.8 seconds.

The velocity of an object is the ratio of its travel distance over a given amount of time. The magnitude and direction are both necessary for the velocity because it is a vector quantity.

Given that an apple suddenly drops a distance of 3.2 m from a tree. If the acceleration due to gravity is 9.8 m/s². The time taken by the apple to reach the ground will be calculated by the formula below:-

Time = √ ( 2s)/g)

Time = √ ( 2 x 3.2 )/9.8)

Time = 0.8 second

As a result, it will take the apple 0.8 seconds to reach the ground.

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Answer:

I think your bones, muscles, and joints your welcome :)

Explanation:

Answer:

It is 6.02 kilograms.

Explanation:

One kilogram is equal to 9.81 Newtons. To convert Newtons to Kilograms,divide by 9.81. For instance, 20 Newtons would be equivalent to 20/9.81 or 2.04 kilograms

Answer:

Mass of object is 0.5kg

Explanation:

Given the following data;

Force = 6N

Acceleration = 12m/s²

Mass =?

Force is given by the multiplication of mass and acceleration.

Mathematically, Force is;

[tex] F = ma[/tex]

Where;

F represents force.

m represents the mass of an object.

a represents acceleration.

Making mass (m) the subject, we have;

[tex]Mass (m) = \frac{F}{a}[/tex]

Substituting into the equation;

[tex]Mass (m) = \frac{6}{12}[/tex]

Mass, m = 0.5kg.

Therefore, the mass of the object is 0.5kg

Answer:

48.5

Explanation:

vf = vi + at

vf = 35 + 4.5(3)

vf = 35 + 13.5

vf = 48.5 m/s

if the boy runs  400m at an average speed of 4.0m/s he runs the first 200m in 40 at the same speed he will cover next 200m in 40 s  and the the average speed is  of 4.0m

Angular speed is a measures of speed of how fast the central angle of a rotating body changes with respect to given time

It mainly implies how quickly the object is  rotating means it is described as the change in the angle of the object per unit of time.

To calculate the speed the value of  angular speed are needed thus  angular speeds formula is used to calculate the distance traveled by an object in terms of rotation and revolutions per unit of time.

The unit of angular speed of an object is denoted as radian per second and Both angular speed, angular velocity are calculated by using the same formula.

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Answer :

beaker A , it is because the temperature increases is higher than beaker B.

Formula

(10°F − 32) × 5/9 + 273.15 = 260.928K

10 degrees fahrenheit = 260.928 kelvins

Formula

(10K − 273.15) × 9/5 + 32 = -441.7°F

10 kelvins = -441.67 degrees fahrenheit

beaker A , 10°F = -12.222 °C

beaker B , 10k = -263.15 °C

Beaker A of water will have a higher temperature than the temperature of beaker B.

To convert the temperature Fahrenheit to Celsius formula is used from the scale Fahrenheit to Celsius. Both scales provide a way to measure the object’s hotness and coldness and are used to measure the temperature. The symbol used to express Fahrenheit is °F while the symbol used for Celsius is °C.

The formula used to change the temperature from Fahrenheit to Celsius as follows:

°C = (°F- 32)5/9

The temperature of beaker A  is increased by 10°F. So the change in temperature in the Celcius scale is :

T(°C) = (10- 32)5/9

T(°C) =  -12.22°C

The temperature of beaker B  is increased by 10 K, then the temperature in Celcius is:

T(°C) = 10 - 273.15

T(°C) = - 263.15°C

Therefore, the temperature of beaker A will be higher after these changes if initially, both are at the same temperature.

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