A ball is projected at an angle 60° with the horizontal with speed 30 m/s . What will be the speed of the ball when it makes an angle 45° with the horizontal?

Question

A ball is projected at an angle 60° with the horizontal with speed 30 m/s . What will be the speed of the ball when it makes an angle 45° with the horizontal? (A) 30m/s (B) 15√2m/s (C) (15/√2)m/s (D) 30√2m/s

Tardigrade Admin · Accepted Answer

Horizontal velocity remains same 30° cos60° =vcos45° ⇒ v=15√2m/s

Q. A ball is projected at an angle $6 0^{\circ}$ with the horizontal with speed $30 m / s$ . What will be the speed of the ball when it makes an angle $4 5^{\circ}$ with the horizontal?

$30 m / s$

$152 m / s$

$\frac{15}{2} m / s$

$302 m / s$

Horizontal velocity remains same $3 0^{\circ} cos 6 0^{\circ} = v cos 4 5^{\circ}$
$\Rightarrow v = 152 m / s$

Q. A ball is projected at an angle 60∘ with the horizontal with speed 30m/s . What will be the speed of the ball when it makes an angle 45∘ with the horizontal?

30m/s

152​m/s

2​15​m/s

302​m/s