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What are the answers on science homework?

I just finished and would like to check my answers.

Find the kinetic energy of a 0.1-kilogram toy truck moving at a speed of 1.1 meters per second.

What is the speed of a 48-kilogram dog running across a lawn with 216 joules of kinetic energy?

A book on a shelf 2.0 meters above the floor has a mass of 1.5 kilograms. What is the gravitational potentialenergy of the book?

Find the mass of a ball on a roof 30 meters high, if the ball’s gravitational potential energy is 58.8 joules.

Which runner has greater kinetic energy: a 46-kilogram runner moving at a speed of 8 meters per second or a 92-kilogram runner moving at a speed of 4 meters per second?

If a 6.0-kilogram box is moved from the floor to a storage compartment 2.0 meters above the floor, by how many joules does its gravitational potential energy change?

A 0.1-kilogram ball rolls across the floor at a speed of 2 meters per second. Another 0.1-kilogram ball rests ona shelf 1 meter above the floor. Which ball has more energy?

Thank you some much your i will be forever thankful

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Just remember KE=1/2mv^2 and GPE = mgh,
I'll do some of them
The first one
Find the kinetic energy of a 0.1-kilogram toy truck moving at a speed of 1.1 meters per second.
KE = 1/2 mv^2
KE = 1/2 (0.1)(1.1)^2
KE = 0.0605 joules of kinetic energy
The second one is different
What is the speed of a 48-kilogram dog running across a lawn with 216 joules of kinetic energy?
Your given the kinetic energy and the mass, so you find the velocity
216 = 1/2(48)(v^2)
v^2 = 9
velocity = 3 (the units are) metres per second squared

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The third one
A book on a shelf 2.0 meters above the floor has a mass of 1.5 kilograms. What is the gravitational potentialenergy of the book?
GPE = mgh
GPE = (1.5)(2)(9.8)
GPE = 29.4 joules
The fourth one
Find the mass of a ball on a roof 30 meters high, if the ball’s gravitational potential energy is 58.8 joules.
58.8 = m(30)(9.8)
mass = 0.2
The mass of the ball is 0.2kg or 200 grams
The fifth one
Which runner has greater kinetic energy: a 46-kilogram runner moving at a speed of 8 meters per second or a 92-kilogram runner moving at a speed of 4 meters per second?
The first guy
KE = 1/2(46)(8^2)
KE = 1472 joules
The second guy
KE = 1/2(92)(16)
KE = 736 joules
Therefore, the first guy has more kinetic energy
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Lol sorry, the answer was too long, try the last two yourself.
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Thanks so much. Turns out I now most of them.
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Oh ok, no worries
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