Question

A plane is flying horizontally at $98m/s$ and releases an object which reaches the ground in 10 seconds. The angle made by it when it hits the ground is

• A. ${30}^{\circ }$
• B. ${45}^{\circ }$
• C. ${60}^{\circ }$
• D. ${75}^{\circ }$

Answer 1

The correct option is B ${45}^{\circ }$

In the horizontal direction, $v_x=u_x=98m/s$
In the vertical direction,
$v_y=u_y+gt=0+9.8\times 10=98m/s$
Hence the angle made by the velocity vector with the horizontal is
$\tan \theta =\frac{v_y}{v_x}=1$
$⟹\theta ={45}^0$