Question

A body thrown vertically upward with an initial velocity $u$ reaches maximum height in 6 second. The ratio of the distances travelled by the body in the first second and seventh second is

• A. 1 : 1
• B. 11 : 1
• C. 1 : 2
• D. 1 : 11

Answer 1

Answer: (B)

Time of ascent $=\frac{u}{g}=6s$
$\Rightarrow u=60m/s$
Distance in first second,
$h_{\text{first }}=60-\frac{g}{2}(2\times 1-1)=55m$
Distance in seventh second will be equal to the distance in first second of vertical downward motion.
$h_{\text{seventh }}=\frac{g}{2}(2\times 1-1)=5m$
$\Rightarrow h_{\text{first }}/h_{\text{seventh }}=11:1$