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(a)Define :Force (b)The velocity -time ...

(a)Define :Force
(b)The velocity -time graph of a car of mass 1000 kg is given below:

(i)When is the maximum force acting on the car>Why?
(ii)What is the retarding force?

Text Solution

Verified by Experts

(b)(i)u=0,v `15ms^(-1)` ,t=4s
acceleration a=`(v-u)/(t)=(15-0)/(4) ms^(-2)`
Force ,F=ma
`1000kgxx(15)/(4)ms^(-2)`
=3750 N
The maximum force acting on the car is 3759 N .
After this ,the car moves with uniform velocity of 15 m `s^(-1)` till 8 ssecond.
(ii)Retardation :u=15 m`s^(-1)` ,v=o t=4 s
The acceleration is negative ,because the velocity of the car is decreasinh retarding force.
F=ma=`1000 kg xx((-15)/(4))ms^(-2)=-3750N`
The magnitude of the retarding force is 3750N
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