Question

A body is projected horizontally with 98 m/s from the top a tower reaches the ground in 10s. Then it strikes the ground at an angle
1) 0⁰
2) 45°
3) 30°
4) 60⁰​

Answer 1

Answer:

30⁰ is correct answer

hope it help you

Answer 2

Given :

Initial velocity of body = 98m/s

Time taken by body to reach the ground = 10s

To Find :

We have to find the angle at which body strikes the ground.

Solution :

❖ First of all we need to find range of the projectile. Here initial velocity and time of flight are given so we will directly apply formula of velocity in order to find range of the projectile$.$

➙ R = u × t

• R denotes range
• u denotes initial velocity
• t denotes time

By substituting the given values;

➙ R = 98 × 10

➙ R = 980 m

Now let's find height of the tower!

➙ t = √2H/g

➙ 10 = √2H/9.8

➙ 100 = 2H/9.8

➙ H = 980/2

➙ H = 490 m

❖ Calculation of angle :

➠ tan θ = H / R

➠ tan θ = 490/980

➠ tan θ = 1/2

➠ θ = tan‾¹ (0.5)

➠ θ = 26.56° ≈ 30°