Question

At a place where the acceleration due to gravity is $10m{s}^{-2}$ a force of $5kg-wt$ acts on a body of mass $10kg$ initially at rest. Find the velocity of the body after $4$ second.

Answer 1

Step 1: Given

Acceleration due to gravity = $10m{s}^{-2}$

Force = $5kg-wt=50N$

Mass of body = $10kg$

Time = $4$ second

Initial velocity = $0$

Step 2: Formula used and calculation

Acceleration of the body = $\frac{Forceonthebody}{massofthebody}$

$$\begin{gathered} \Rightarrow a=\frac{50}{10} \\ \Rightarrow a=5m{s}^{-2} \end{gathered}$$

Now, using equation of the motion

$$\begin{gathered} v=u+at \\ \Rightarrow v=0+5\times 4 \\ \Rightarrow v=20m{s}^{-1} \end{gathered}$$

Hence, velocity of the body after $4$ second is $20m{s}^{-1}$.