Question

An aircraft flying horizontally with the speed $480\, kmh ^{-1}$ releases a parachute at a height of $980 \,m$ from the ground. It will strike the ground at (use, $g=10 \,ms ^{-2}$ )

• A. $1\, km$
• B. $2\, km$
• C. $2.8 \,km$
• D. $1.867 \,km$

Answer 1

Answer: (D)

Time taken by the parachute to fall through a height $h$ of $980\, m$
$t=\sqrt{\frac{2 h}{g}}=\sqrt{\frac{2 \times 980}{10}}=14 \,s$
Distance at which the parachute strikes the ground
$=$ Horizontal velocity $\times t$
$=480 \times 14 \times \frac{1}{3600}$
$=\frac{6720}{3600}=1.867\, km$