33(b) 1sec
wid itz engine delievering max (and constant ) power, a sports car accelerates from 0 to 60 mph in 9 seconds. how long did it take 2 reach 20 mph??
a) 4.5s
b) 1s
c) 3s
d) 6s
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6 Answers
33Fv=K
mvdv/dt=K
vdv=(K/m)dt
0∫60vdv=k'0∫9dt
k'=K/m=200
now
0∫20vdv=k'0∫tdt
t=1 sec
3much simpler approach.........[same almost]
dW/dt = P .........
W = Pt ...........
1/2(60)^2 (m) = 9P
1/2(20)^2(m) = tP .......
divide both eqxns ......
t = 1 s [1] .......
priyam ... kahan se naya smiley access kiya ????????????????
33Image link is there just by the side of hide...
use this link..
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