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5 votes
3. A cart at rest at the top of a roller coaster has 1000 J of

potential energy. The roller coaster goes down one hill and up
another smaller hill. If it has 400 J of potential energy at the
top of the second hill, how much kinetic energy does it have?
A)OJ B) 250 J
C) 600J
D) 1400 J E) 400000 J

2 Answers

3 votes

Answer:

i think C

Step-by-step explanation:

User Daniel Thompson
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6 votes

Answer:

600J

Step-by-step explanation:

Assuming no energy is lost and perfect transfers.

On the top of the first hill,
E_(k)+E_(p)=1000 - however there is no Kinetic Energy so -
E_k = 0

On the second hill, the total amount of energy is still the same (1000) - this time we have a smaller amount of potential energy. We can rearrange to get
E_k=1000-400

User Tigt
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3.5k points