The force required to stop a car of mass $$800\,kg,$$ moving at a speed of $$20\,m{s^{ - 1}}$$ over a distance of $$25\,m$$ in $$2.5\,\sec$$ is
A.
$$1200\,N$$
B.
$$6400\,N$$
C.
$$1600\,N$$
D.
$$1800\,N$$
Answer :
$$6400\,N$$
Solution :
As we know, $$\left| a \right| = \left| {\frac{{{v^2} - {u^2}}}{{2S}}} \right| = \frac{{400}}{{50}} = 8\,m/{s^2}.$$
So force required $$ = F = ma$$
$$ = 800 \times 8 = 6400\,N$$
Releted MCQ Question on Basic Physics >> Impulse
Releted Question 1
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