Question

A body is projected vertically upward with speed $40m/s$. The distance travelled by the body in last 2 second of the journey is $[g=10m/s^2]$

• A. $10\text{m}$
• B. $5\text{m}$
• C. $60\text{m}$
• D. $15\text{m}$

Answer 1

The correct option is C $60\text{m}$

As the motion occurs under gravity,
Time taken for total journey is $8\text{s}$
So, the distance travelled in last 2 second is equal to distance travelled in first 2 second.
therefore
$x_1=x_2=ut-\frac{1}{2}g{t}^2$
$=40\times 2-\frac{1}{2}\times 10\times 2^2$
$x_1=x_2=60\text{m}$
$x_1=60\text{m}$