Question

A ball is thrown vertically upwards with a velocity of 49m/s. calculate

(1) the maximum hight to which it rises
(2) the total time it takes to return to the surface of the Earth ​

Answer 1

Answer:

Initial velocity of the ball (u) = 49m/s. The velocity of the ball at maximum height (v) = 0. Let us considered the time taken is t to reach the maximum height H. (2) The total time ball takes to return to the surface of the earth = 5 + 5 = 10 sec.

Answer 2

Answer:

Given parameters

Initial velocity of the ball (u) = 49m/s.

The velocity of the ball at maximum height (v) = 0.

g = 9.8m/s2

Let us considered the time taken is t to reach the maximum height H.

Consider a formula,

2gH = v2 – u2

2 × (- 9.8) × H = 0 – (49)2

– 19.6 H = – 2401

H = 122.5 m

Now consider a formula,

v = u + g × t

0 = 49 + (- 9.8) × t

– 49 = – 9.8t

t = 5 sec

(1) The maximum height to ball rises = 122.5 m

(2) The total time ball takes to return to the surface of the earth = 5 + 5 = 10 sec.