Question about (KINETIC ENERGY AND WORK)

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The discussion revolves around two multiple-choice questions related to kinetic energy and work. The first question involves a 50-N force acting on a 2-kg object for 2 seconds, with the answer being 2500W, calculated using the distance derived from the force and time. The second question also features a 50-N force on a 2-kg crate, with the answer being 500W when the crate has moved 2 meters. Participants express confusion about the calculations due to the lack of distance in the first problem and velocity in the second. Clarifications are provided, leading to a resolution for the first question, while the second remains under discussion.
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Homework Statement


hi guys how are you?? ,, there are 2 MC (Multiple choices question)
1- A 50-N force is the only force on a 2-kg object that starts from rest. When the force has been acting for 2 s the rate at which it is doing work is:(Ans:2500W)

2-A 50-N force is the only force a 2-kg crate that starts from rest. At the instant the object has gone 2m the rate at which the force is doing work is:(Ans:500W)

The Attempt at a Solution


i tried several ways but the problem is i know only 2 equations about power
one is P=W/t and P=Fv ,, in problem 1 there is no distance and in 2 there is no velocity, i didn't understand the questions in the first place(cant imagine it) ,, is the force acting horizontally or vertically ,, can anyone help me please before the exam,,
 
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For the first one, you can calculate the distance based on the information given. Note that the object is in something like freefall, since the 50N force is the only thing acting on it.
 
thanks ,, first one solved :) ,, still with the second...
 
Lord Dark said:

Homework Statement


hi guys how are you?? ,, there are 2 MC (Multiple choices question)
1- A 50-N force is the only force on a 2-kg object that starts from rest. When the force has been acting for 2 s the rate at which it is doing work is:(Ans:2500W)

2-A 50-N force is the only force a 2-kg crate that starts from rest. At the instant the object has gone 2m the rate at which the force is doing work is:(Ans:500W)

Just curious what the other multiple choices were.
 
LowlyPion said:
Just curious what the other multiple choices were.

in 1)
A. 75W
B. 100W
C. 1000W
D. 2500W
E. 5000W

2)
A. 2.5W
B. 25W
C. 75W
D. 100W
E. 500W
 
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