science
posted by Dave .
1. How much potential energy does a 5kg block have if it is 2m above the ground?
2. What is the mass of an object that has 40J of potential energy and is 10m above the ground?
3. What is the weight of an 8kg object?
4. How much work does it take to lift an 8kg object 2m?
5. How high up must you lift a 12kg object to give it 72J of potential energy?
6. A 5kg ball is rolling along the floor with a velocity of 3m/s. What is its kinetic energy?
7. The ball from question 6 speeds up to 6m/s. What is its new kinetic energy?
8. Compare your answers to questions 6 and 7. What do you notice about the kinetic energy when an object doubles its velocity?

Use the formulas:
(Potential energy) =
M g H = (Mass)*(g)*(height)
Weight = M*g
Kinetic energy of a rolling solid ball = (7/10) M V^2
(This includes the energy associated with rotation)
Show your work if you need further assistance. 
1.Given :h=2m,m=5kg potential energy=mgh=5Ã—10Ã—2=100 J

2.Given :potential energy=40J,h=10m Potential Energy =mgh since,
m=gh/P.E.=10*10/40J =20/40J =0.5kg 
what does gravity = ?

reply plz.

gravity = 9.8 on earth

thanks sky reaper.
5*9.8*2=98 
ok
Respond to this Question
Similar Questions

physics
Object A has a gravitational potential energy of 24 joules when it rests on a shelf 5 m above the ground. Object B has a mass that is three times the mass of Object A. What would be the gravitational potential energy of object B when … 
physics
a 2 kg object is released from rest from a height of 10 m above the ground.calculate the kinetic energy at the moment it reaches 4 m above the ground with potential energy 200J 
science
A 4kg block is sitting on the floor. (a) How much potential energy does it have? 
science
How much work does it take to raise a 3kg object 5m into the air? 
PHYSICS(URGENT)
A particle has a mass of 5kg. It is held at a height of 3 metres above the ground. Find: a.Its potential energy b.It’s kinetic energy when is hits the ground c.The speed with which the particle hits the ground 
Physical science
What is the gravitational potential energy of a 5kg object resting 3m above the ground? 
Physics
A model rocket has a mass of 3.00 kg. It is fired so that when it is 220 m above the ground it is travelling vertically upward at 165 m/s. At that point its fuel runs out so that the rest of its flight is without power. Assume that … 
science
an object has a potential energy of 100 J when it is 10 m above the ground. if it were to fall without friction what would its kinetic energy be the instant it hits the ground 
Physics
A classmate throws a 1.1kg book from a height of 1.3 m above the ground straight up into the air. The book reaches a maximum height of 4.0 m above the ground and begins to fall back. Assume that 1.3 m above the ground is the reference … 
science
An object has a gravitational potential energy of 24 joules when it rests on a shelf 3 m above the ground. What would be its gravitational potential energy when it is lowered to a shelf 1 m above the ground?