Question

When two bodies move uniformly towards each other, the distance decreases by $6m{s}^{-1}$.If both bodies move in the same direction with the same speed as above the distance between them increases by $4m{s}^{-1}$. Then the speed of the two bodies are

• A. $3m{s}^{-1}$ and $3m{s}^{-1}$
• B. $4m{s}^{-1}$ and $2m{s}^{-1}$
• C. $5m{s}^{-1}$ and $1m{s}^{-1}$
• D. $7m{s}^{-1}$ and $3m{s}^{-1}$

Answer 1

Answer: (C)

$5m{s}^{-1}$ and $1m{s}^{-1}$

Given, Distance decreases with $6m/s$ Distance is increases $=4m/s$

Let $v_1,V_2$ is the velocity

So the relative velocity is

$v_1+v_2=6m/s.....1$

$v_1-v_2=4m/s...........2$

Adding equation 1 and 2 then we get,

$2v_1=10m/s\Rightarrow v_1=5m/s$

Put this value in equation 1 then we get,

$v_1+v_2=6\Rightarrow v_2=6-5=1m/s$