A ball is thrown horizontally from the top of a tower of height 8 m. It touches the ground at a distance of 90 m from the foot of the tower. The initial velocity of the body is:

Question

A ball is thrown horizontally from the top of a tower of height 8 m. It touches the ground at a distance of 90 m from the foot of the tower. The initial velocity of the body is: (A) 60 m/s (B) 70 m/s (C) 69.75 m/s (D) None

Tardigrade Admin · Accepted Answer

According to the relation R = u √(2 h / g ) ⇒ u = R √( g /2 h )=90 √(10/2 × 8) u =90 √(10/16) ⇒ u =(90/4) √10 ⇒ u =(90/4) × 3.1 u =69.75

Q. A ball is thrown horizontally from the top of a tower of height $8 m$ . It touches the ground at a distance of $90 m$ from the foot of the tower. The initial velocity of the body is:

$60 m / s$

$70 m / s$

$69.75 m / s$

None

According to the relation
$R = u \frac{2 h}{g}$
$\Rightarrow u = R \frac{g}{2 h} = 90$
$\frac{10}{2 \times 8}$
$u = 90 \frac{10}{16}$
$\Rightarrow u = \frac{90}{4} 10$
$\Rightarrow u = \frac{90}{4} \times 3.1$
$u = 69.75$

Q. A ball is thrown horizontally from the top of a tower of height 8m. It touches the ground at a distance of 90m from the foot of the tower. The initial velocity of the body is:

60m/s

70m/s

69.75m/s