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Help with 1st Year Physics Question (Engineering)

murria · 2015-03-03 22:51:26

My son is looking for help with this question, can anyone please. A bus with a mass of 14000 kg travels along a horizontal road and decelerates from 60 km.h-1 to 40 km.h-1 over a distance of 50m. The change in kinetic energy is; [____] 0.35 KJ [____] 20 MJ [____] 1.08 MJ [____] 50 m

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03-03-2015 11:51pm

#1

murria

Registered Users Posts: 395 ✭✭

Join Date: December 2010

Posts: 390

My son is looking for help with this question, can anyone please.

A bus with a mass of 14000 kg travels along a
horizontal road and decelerates from 60 km.h-1 to
40 km.h-1 over a distance of 50m. The change in
kinetic energy is;
[____] 0.35 KJ
[____] 20 MJ
[____] 1.08 MJ
[____] 50 m

0

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#2 04-03-2015 1:01am
citrus burst

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Join Date: July 2011

Posts: 144

There is a formula for kinetic energy. The change is simple the difference between the two kinetic energies.

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#3 10-03-2015 4:43pm
chakotha

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Join Date: June 2002

Posts: 881

And convert the km.h-1 into m.s-1 first.

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