Question

Solve this question with accurate steps.

The answer to check are-
i. 19.6 m
ii. 29.4 m/s
iii. 5 s
But provide procedure.​

Answer 1

Answer:

Explanation:

2nd part:

Initial Velocity(u)= 19.6m/s.

Since, we throw the ball vertically upwards, Final velocity(v) is 0.

Acceleration(top of the tower)= -9.8m/s..

Use, v=u+(-g)t

=> 0= 19.6-9.8t

=> t= 2sec..

W.K.T,

h= ut+1/2gt^2

24.5= 19.6t+9.8t^2/2

=> 4.9t^2+19.6t-24.5=0

By solving this eqn,

we get t= 1sec.....

We already know that,  Time taken to go up= Time taken to go down= 2sec

So, We have to add 2+2+1(it is remaining time)= 5sec.....

We can take the time to move downwards as 2+1 = 3sec...

(Ball moving downwards)

Here, Now u is 0

Use the formula, v= u+gt

=> v= 0+9.8*3

=> v= 29.4m/s

We can derive the formula of h= u^2/2g by,

We are already familiar with the formula of v^2=u^2+2gh

Since, it goes above, v=0, a is negative.....

=> 0= u^2-2gh

=> h= u^2/2g.....

So, h= 19.6^2/2*9.8= 19.6m.....