Laws Of Motion Question 5

Question 5 - 29 January - Shift 2

Force acts for $20 s$ on a body of mass $20 kg$,starting from rest, after which the force ceases and then body describes $50 m$ in the next $10 s$. The value of force will be :

(1) $40 N$

(2) $5 N$

(3) $20 N$

(4) $10 N$

Show Answer

Answer: (2)

Solution:

Formula: Second Law Of Motion

$50=V \times 10$

$V=5 m / s$

$V=0+a \times 20$

$5=a \times 20$

$a=\frac{1}{4} m / s^{2}$

$F=ma=20 \times \frac{1}{4}=5 N$