Question

the speedometer of a car reads 36km/hr in 5 min just after start . find acceleration
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Answer 1

Given:

Time = t= 9.45 -9.25=20min= 20x60 seconds

Initial velocity = 36km/h = 36x 5/18=10 m/s

Final velocity = V= 72km/h=72x 5/18=20m/s

Acceleration= a=V-u/t

=20-10/20x60

=10/20x60

=1/120

=0.008m/s2

THEREFORE acceleration of the car is 0.008m/s2

From Second equation of motion:

V^2-u^2=2as

S=V^2-u^2/2a

S=(20×20)-(10×10)/2*0.008

S=(400_100)/2*0.008

=300/2×0.008 =150/0.008 =150*1000/8 =18.75x 1000 =1875000/100=18750m Magnitude of displacement is 18750m

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HOPE IT'S HELPS