Question

A boat is moving with velocity v = 2 m/s w.r.t. river at an angle θ = 30°. Velocity of river is u = 4 m/s. A man at the bank is moving with velocity v0 as shown in figure. If the boat is moving perpendicularly to the bank w.r.t the man, then v0 is

Answer 1

The velocity of the man is 1 m/s.

The velocity of the boat, v = 2 m/s

The angle created by the boat with respect to the river, θ = 30°

Velocity of the river, u = 4 m/s

Velocity of the man at the bank = v₀

The boat is appearing perpendicular to the man.

∴ The angle created by the boat w.r.t. the man = 60°

∴ The velocity of the man will be = 2 Cos 60°

                                                      = 2× $\frac{1}{2}$

                                                      = 1 m/s

∴ The value of v₀ will be 1 m/s.