Question

batsman hit a ball giving it an initial velocity of 4 m/s. The ball moved with an

acceleration of 0.2 m/s2

. It took the ball 15 seconds to reach the boundary.

(3 marks)

a) Calculate the distance travelled by the ball and its velocity when it crosses the

boundary.

b) If we had to reduce the time it took the ball to reach the boundary by half, what

acceleration would be needed​

Answer 1

Answer:

A. Given: u =4m/s, t=15s,a=0.1"m/s2

s=ut+1/2at2

=4*15+1/2*0.1*15*15

=60+21.5

=81.5m

Therefore distance covered by the ball is 81.5m

And final velocity is

v=u+at

=4+0.2*15

=4+3

=7m/s

i.e. Final velocity is 7m/s

B. a'=v-u/t'

a'=7-4*1*15

2

a'=3*15

2

a'=45 = 22.5m/s2

2 Therefore acceleration of the ball when time taken is reduced by half is 22.5m/s2

Hope this will help you