Question

A wicket keeper catches a ball moving at 30 m/s. If he does not moves his hand the ball comes to rest in his glove. what is the average acceleration ?​

Answer 1

$\huge{\underline{\underline{\boxed{\sf{\purple{Answer ࿐}}}}}}$

While catching a fast moving cricket ball, a fielder in the ground gradually pulls his hand backward with the moving ball, In doing so, the fielder increases the time during which the high velocity of the moving ball decrease to zero.

Thus, the acceleration of the ball is decreased and therefore the impact of catching the fast moving ball is also reduced.

If the ball stopped suddenly then its high velocity is decreased to zero in a very short interval of time.

Thus, the rate of change of momentum of the ball will be large. Therefore, a large force would have to be applied for holding the catch that may hurt the palm of the fielder.

Answer 2

Answer:

⠀

The average acceleration is – 45000 m/s$^{2}$.

⠀

Explanation:

⠀

Given data:

⠀

• Distance (S) = 1 cm = 0.01 m

• Initial velocity (u) = 30m/s

• Final velocity (v) = 0

• time (t) = x

⠀

To find:

⠀

Average acceleration

⠀

Solution:

⠀

We know that,

2as = v$^{2}$ – u$^{2}$

⠀

Now substitute the known values.

2 × 0.01 × a = 0 – 30$^{2}$

→ 0.028a = – 900

→ a = –900/0.02 = – 45000

→ a = – 45000 m/s$^{2}$

⠀

Thus, the average acceleration will be – 45000 m/s$^{2}$.

⠀

___________________________________

⠀

More formulas:

⠀

First equation of motion:

• v = u + at

Second equation of motion:

• S = ut + 1/2at$^{2}$

Third equation of motion:

• v$^{2}$ = u$^{2}$ + 2as

_________________________