Question

A food packet is released from a helicopter rising steadily at the speed of $2 \,ms ^{-1}$. What is the velocity of the packet after $2\, s$ ? $\left(g = 10 \,ms ^{-2}\right)$

• A. $18\, ms ^{-1}$
• B. $20\, ms ^{-1}$
• C. $22\, ms ^{-1}$
• D. $98\, ms ^{-1}$

Answer 1

Answer: (A)

Let us take down as +ve, here,
$u = -2\, ms ^{-1}, a = +10\, ms ^{-2}, t=2\, s$
As $v = u+a t \Rightarrow v = (-2)+(10)(2)$
$v=+18\, ms ^{-1}$