The force required to stop a body of mass $10 \mathrm{~kg}$ moving along a straight line path with a…
The force required to stop a body of mass $10 \mathrm{~kg}$ moving along a straight line path with a velocity of $10 \mathrm{~ms}^{-1}$ in a time of $10 \mathrm{~s}$ is
$10 \mathrm{~N}$
$1000 \mathrm{~N}$
$100 \mathrm{~N}$
$1 \mathrm{~N}$
Solution
Mass, $\mathrm{m}=10 \mathrm{~kg}$ Initial velocity, $u=10 \mathrm{~m} / \mathrm{s}$ Time, $\mathrm{t}=10 \mathrm{sec}$ final velocity, $\mathrm{V}=0$ using Newton's IInd law
$
\begin{aligned}
& F=m a=m\left(\frac{V-u}{t}\right) \\
& =\frac{10 \times 10}{10}=10 \\
& F=10 N
\end{aligned}
$