A body of mass 2 kg is moving with a momentum of 10 kg ms-1. The force needed to increase its kinetic energy by four times in 10 seconds is

Question

A body of mass 2 kg is moving with a momentum of 10 kg ms-1. The force needed to increase its kinetic energy by four times in 10 seconds is (A) 2 N (B) 4 N (C) 1 N (D) 0.5N

Tardigrade Admin · Accepted Answer

K E=(P2/2 M) ⇒ P momentum two times ⇒ Δ P=P'-P=P=F × t 10=F × 10 or F=1 N

Q. A body of mass $2 k g$ is moving with a momentum of $10 k g m s^{- 1}$ . The force needed to increase its kinetic energy by four times in $10$ seconds is

$2 N$

$4 N$

$1 N$

$0.5 N$

$8 N$

$K E = \frac{P ^{2}}{2 M}$
$\Rightarrow P$ momentum two times
$\Rightarrow Δ P = P^{'} - P = P = F \times t$
$10 = F \times 10$
or $F = 1 N$

Q. A body of mass 2kg is moving with a momentum of 10kgms−1. The force needed to increase its kinetic energy by four times in 10 seconds is

2N

4N

1N

0.5N

8N

KE=2MP2​ ⇒P momentum two times ⇒ΔP=P′−P=P=F×t 10=F×10 or F=1N