Question

obtain the expression for time of flight

Answer 1

Time of flight: It is the total time for which the projectile remains in air. We know, at the end of time of flight, the projectile reaches the point on the ground. So, vertical height gained by the y = 0.

From vertical equation of motion, we have:

$$y = (usin \theta )T – \frac{1}{2}gT^2 $$

Now,

$$0 = (usin \theta )T – \frac{1}{2}gT^2 $$

$$\therefore T =  \frac{2usin \theta }{g}…….(i)$$

Equation (i) gives the time of flight of the projectile for velocity of projection u at an angle θ.