Question

A constant retarding force of 100N is applied on a body of mass 10 kg moving initially with speed 30 m/s. what is the retardation of body

Answer 1

mass of body =10kg
speed=30m/s

F=MA
-100N=10a
-10m/s ^2 =a

retardation=-(a)
=-(-10)
10m/s

Answer 2

Answer:-

it takes 3 second for body to stop.

Explanation:-

Given:-

Final velocity (v) =0

Initial velocity (u)= 30 m/s

Force( F)= 100 N

Mass of body (m)= 10kg

Solution:-

$\bf{retardation \:(a) = \frac{F}{m} } \\ \\ \implies \: \frac{100}{10} = 10 \: \: \: \frac{m}{ {s}^{2} } \\ \\ \red{ \bf{now \: using \: first \: equation \: of \: motion}} \\ \\ \implies \bf{ v = u + at} \\ \\ \implies \: \bf{ 0 = 30 + ( - 10)t }\\ \\ \implies \: \bf{10t = 30 }\\ \\ \implies \: \bf{t = 3 \: s}$

Hence, it takes 3 second for body to stop.