(1/2) m v^2 = m g (45-5)
v^2 = 2 (9.81)(40)
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Second question has no real answer unless we assume that the potential energy is zero at the ground level.
ONLY changes in potential have meaning,and you must always define a base
If we ASSUME U = 0 at
ground
then at 5 meters up
U = potential energy = m g h
= 5 9.81 * 5 Joules
A roller coaster cart is pulled up to the top of the hill 45 m high before it plunges down to its lowest point, 5 m above the ground. What is the cart’s speed at this point? What is its potential energy if the mass of the object is 5 kg?
1 answer