Two blocks A and B are connected by a massless string (shown in the figure). A force of 30 N is applied on block B . The distance travelled by centre of mass in 2 s starting from rest is

Question

Two blocks A and B are connected by a massless string (shown in the figure). A force of 30 N is applied on block B . The distance travelled by centre of mass in 2 s starting from rest is <img class="img-fluid question-image" alt="Question" src="https://cdn.tardigrade.in/q/nta/p-29u6itptryvtdtav.jpg" /> (A) 1m (B) 2m (C) 3m (D) 4m

Tardigrade Admin · Accepted Answer

The acceleration of the centre of mass is aC M=(F/mA + mB) =(30/10 + 20)=1 m s- 2 ∴ s=(1/2)acmt2=(1/2)× 1× 22=2 m

Q. Two blocks $A$ and $B$ are connected by a massless string (shown in the figure). A force of $30 N$ is applied on block $B$ . The distance travelled by centre of mass in $2 s$ starting from rest is

$1 m$

$2 m$

$3 m$

$4 m$

The acceleration of the centre of mass is
$a_{CM} = \frac{F}{m _{A} + m _{B}}$
$= \frac{30}{10 + 20} = 1 m s^{- 2}$
$∴ s = \frac{1}{2} a_{c m} t^{2} = \frac{1}{2} \times 1 \times 2^{2} = 2 m$

Q. Two blocks A and B are connected by a massless string (shown in the figure). A force of 30N is applied on block B . The distance travelled by centre of mass in 2s starting from rest is

1m

2m

3m

4m