Question

please solve the question

Answer 1

option (3)

is the option

Answer 2

Answer: option 2) 0.6 ms⁻²

Explanation:

Let the magnitude of force applied by each person be F

It is given that when two persons apply force, the block moves in the same direction as of force at constant velocity. This means that there is no net force acting on the block.

Hence, this force would be equal to frictional force (f):

f = 2 F

When 3 person push the block, it moves with acceleration 0.2 m/s²

⇒3 F - f = m×0.2 m/s² ⇒ 3 F - 2 F = 0.2 × m

⇒mass of the block, m = 5 F

when 5 person push the block, we need to find the acceleration caused:

5 F - 2 F = m a ⇒ 3 F = 5 F×a

⇒a = 3/5 m/s² = 0.6 m/s²

Hence, the magnitude of the acceleration of the block when five persons push the block is 0.6 m/s²