A stone is projected from the ground with velocity 50 m / s at an angle 30° with horizontal. It crosses a wall after 3 s. How far beyond the wall the stone will strike the ground? (g=10 m / s 2)

Question

A stone is projected from the ground with velocity 50 m / s at an angle 30° with horizontal. It crosses a wall after 3 s. How far beyond the wall the stone will strike the ground? (g=10 m / s 2) (A) 90.2 m (B) 12.5 m (C) 86.5 m (D) 125 √3 m

Tardigrade Admin · Accepted Answer

Time, T=(2 u sin θ/g)=(2 × 50 × sin 30°/10) =(2 × 50 × (1/2)/10)=5 s Time spent after crossing the wall, t2=5-3=2 s ∴ Distance, x2=u cos θ × 2=50 × cos 30° × 2 =86.5 m

Q. A stone is projected from the ground with velocity $50 m / s$ at an angle $3 0^{\circ}$ with horizontal. It crosses a wall after $3 s$ . How far beyond the wall the stone will strike the ground? $(g = 10 m / s^{2})$

$90.2 m$

$12.5 m$

$86.5 m$

$1253 m$

Time, $T = \frac{2 u s i n θ}{g} = \frac{2 \times 50 \times s i n 3 0 ^{\circ}}{10}$
$= \frac{2 \times 50 \times \frac{1}{2}}{10} = 5 s$ Time spent after crossing the wall,
$t_{2} = 5 - 3 = 2 s$
$∴$ Distance,
$x_{2} = u cos θ \times 2 = 50 \times cos 3 0^{\circ} \times 2$
$= 86.5 m$

Q. A stone is projected from the ground with velocity 50m/s at an angle 30∘ with horizontal. It crosses a wall after 3s. How far beyond the wall the stone will strike the ground? (g=10m/s2)

90.2m

12.5m

86.5m

1253​m