Question

A particle of mass 1 kg is projected at an angle 45 degree to the horizontal with an initial velocity of 20m/s. What is change in momentum during its time of flight?

Answer 1

Answer:

The answer is 14.14 m/s

Explanation:

According to the problem the mass of the particle ,m = 1 kg

The initial velocity v = 20 m/s

The particle is making an angle of 45 degree with horizontal

Now we can that the velocity v has two components: v cos 45 °+ v sin 45 °

Therefore the final velocity = v cos45 °

Therefore change in momentum,

Δ p = mass x (final velocity - initial velocity)

            = 1 x (v cos45 ° - (v cos 45 °+ v sin 45 °))

              = 1 x (-v sin45 °)

             = 1 x (-20 x 1/√2)

             = 14.14 m/s