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3 years ago

A book on a 2-meter high shelf has a mass of 0.4 kg. What is its potential energy?

Physics

2 answers:

poizon [28]3 years ago

6 0

Answer:

$\boxed {\boxed {\sf 7.84 \ Joules}}$

Explanation:

The formula for potential energy is:

$PE=m*g*h$

where m is the mass, g is the gravitational acceleration, and h is the height.

The mass of the book is 0.4 kilograms. The gravitational acceleration on Earth is 9.8 m/s². The height of the book is 2 meters.

$m=0.4 \ kg \\g=9.8 \ m/s^2 \\h=2\ m$

Substitute the values into the formula.

$PE=(0.4 \ kg)(9.8 \ m/s^2)(2 \ m)$

Multiply the first two numbers.

0.4 kg*9.8 m/s²= 3.92 kg*m/s²
If we convert the units now, the problem will be much easier later on.
1 kg*m/s² is equal to 1 Newton. So, our answer of 3.92 kg*m/s² is equal to 3.92 N

$PE=(3.92 \ N )(2 \ m)$

Multiply.

3.92 N* 2 m=7.84 N*m
1 Newton meter is equal to 1 Joule (this is why we converted the units).
Our answer is equal to 7.84 Joules.

$PE=7.84 \ J$

Aliun [14]3 years ago

4 0

Answer:

7.84 is your answer ok bye

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4 years ago

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An object has a mass of 6kg. calculate it's gpe

m_a_m_a [10]

Explanation:

When m=mass

G=acceleration due to gravity

H=height

Using formula

Mgh

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3 years ago

If an 83.00 g sample of Iron has a starting temperature of 297K and an ending temperature of 329K how much heat will be lost fro

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Question 1 :

m = mass of iron sample = 83

c = specific heat of iron sample = 0.450 J/g ⁰C

T₀ = initial temperature = 297 K

T = final temperature = 329 K

Q = heat lost

Heat lost is given as

Q = m c (T - T₀)

inserting the values

Q = (83) (0.450) (329 - 297) = 1195.2 J

Question 2 :

m = mass of sample = 59 g

c = specific heat of sample = ?

ΔT = change in temperature = 85 c

c = specific heat

Q = heat absorbed = 4814.4 J

Heat absorbed is given as

Q = m c

inserting the values

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Question 3 :

m = mass of sample = 55 g

c = specific heat of sample = ?

T₀ = initial temperature = 78 c

T = final temperature = 95 c

Q = heat absorbed = 3908.3 J

Heat absorbed is given as

Q = m c (T - T₀)

inserting the values

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3 years ago

19. Two objects of equal masses collide head-on while moving in the opposite directions and join together. Show that the fractio

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Answer:

Explanation:

mass of each object = m

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