I state my problen in my solution(adsbygoogle = window.adsbygoogle || []).push({});

A big gun had a range of 120 km, a 37.5 m barrel, a muzzle velocity of 1550 m/s and fired a 120 kg shell.

a) If you assume the shell’s acceleration to be constant, what maximum power was transferred to the shell as it travelled along the barrel? [5 Marks]

b) What average power was transferred to the shell? [3 Marks

MY solution

okay so i went about it finding acceleration

u=0

v=1550

s=37.5

m=120

v^2=u^2+2as

a=(v^2-u^2)/(2s)

so now i have a=32033.33m/s^2

then using Newtons law

F=ma

F=120*32033.33

then

F=3844000N

W=Fd

this is myfirst questionis it fair to say d=37.5m or is it 120km??

well thats what i have done

W=144150000J

P=w/t

second questionhow do i find time?

third questionis the above finds the total power yes? how do i find max power, does it mean its the power at a point? and is average pwoer just total power/distance? to find part b

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# Homework Help: Dymanics motion/energy/power, any help would be great

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