Question

An archer shoots an arrow from a height 4.2 m vertical height from the ground with a speed 40m/s and at an angle 30° to horizontal level Determine the horizontal distance R' covered by the arrow when it hits the ground.(Let g=10m/s²)
Ans 84√3

Answer 1

$$h+v\sin{30}t-0.5gt^2=0$$

$$4.2+40\sin{30}t-0.5(10)t^2=0$$

$$t=4.2\ s$$

So,

$$R=v\cos{30}t=40\cos{30}(4.2)=84\sqrt{3}\ m$$