Question

a boy of mass 40 kg is standing in a boat at a distance of 20m from the shore. the mass of the boat is 160kg. The boy moves 4m on the boat in a direction away from the shore . The distance of the boy , now from the shore is?​

Answer 1

Refer to the above attachment

Answer 2

Given:

a boy of mass 40 kg is standing in a boat at a distance of 20m from the shore. the mass of the boat is 160kg. The boy moves 4m on the boat in a direction away from the shore.  

To find:

The distance of the boy, now from the shore is?​

Solution:

From given, we have,

Let the boat moves a distance x away from shore.

Then net displacement of boy towards shore = 8 − x

Now apply : m1 x1 = m2 x2

⇒ 160x = 40 (4 − x)  

⇒ 160x = 160 - 4x

⇒ 160x + 4x = 160

⇒ 200x = 160

⇒ x = 0.8 m

Distance of boy from shore = 20 − (4 − x)  

= 20 - (4 - 0.8)  

= 16.8 m .

Therefore, the distance of the boy, now from the shore is 16.8 m