Question

the reflection surface of the plane mirror is vertical if a particle is projected in a vertical plane which is also perpendicular to the mirror the initial velocity of the particle is 10 metre per second and the angle of projection is 60 degree the point of projection is at a distance of 5 metre from the mirror the particle moves towards the mirror just before the particle touches the mirror the velocity of approaches of the particle and its image is​

Answer 1

$\huge{\mathfrak{\blue{\underline{\underline{Solution:-}}}}}$

Horizontal component of the velocity is 10 cos (60) = 5

And vertical component is 10 sin (60) = 8.66

The particle will touch the mirror after $\bf{\frac{5}{5}}$ = 1 s.

In this time vertical velocity will be v = u - gt

                                                            = 8.66 - 9.8 × 1

                                                            = -1.14.

Now the relative velocity will be due to horizontal component of the particle. Since the vertical velocity will be same. So the relative velocity of the particle is 2 × 5 = 10 m/s.