Currently I am learning about energy, but I am having trouble doing this problem.
How much work must be done to accelerate 800000 kg train: a) from 10 m/s to 15 m/s; b)from 15 m/s to 20 m/s; c) to stop an initial speed of 20 m/s?
It would be much appreciated if someone could break down how to do this problem. Thank you :)
How much work must be done to accelerate 800000 kg train: a) from 10 m/s to 15 m/s; b)from 15 m/s to 20 m/s; c) to stop an initial speed of 20 m/s?
It would be much appreciated if someone could break down how to do this problem. Thank you :)
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In this kind of problems, the work done equals the change in kinetic energy.
a) delta KE = mVf^2 / 2 - mVI^2 /2 = (8x10^5)(15^2)/2 - (8x10^5)(10^2)/2 = 5x10^7 J
Now you can answer questions (b) and (c)
a) delta KE = mVf^2 / 2 - mVI^2 /2 = (8x10^5)(15^2)/2 - (8x10^5)(10^2)/2 = 5x10^7 J
Now you can answer questions (b) and (c)
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first ans a =
50000000 units
50000000 units