Question

A ball is thrown vertically in the air at 120 m/s. second after 3 seconds, another ball is thrown vertically. What velocity must be second ball have to pass the first ball at 100 m from the ground.​

Answer 1

Answer:

Given:-

• A ball is thrown vertically in the air at 120 m/s.
• After 3 seconds another ball is thrown vertically.

To find:-

Velocity of the second ball to pass the first ball at 100 m from the ground.

Solution:-

The first ball will be 100 m from the ground at:

$100 = 120t - 4.9t {}^{2}$

$\Longrightarrow \: 4.gt {}^{2} = - 120t + 100 = 0$

$\Longrightarrow \: t \: = 23.63 \: seconds$

Then, the second ball has to be at 1000 m at 23.63 – 3 = 20.63 sec.

$\Longrightarrow100 = 20.63v - 4.9(20.63) {}^{2} \\ \\\Longrightarrow20.63v - 2085.42481 \\ \\\Longrightarrow20.63v = 2185.42481 \\ \\ \Longrightarrow \: v = 105.9343 \: \frac{m}{s}$

Thus, initial velocity of the second ball = 105.9383

Answer 2

Answer:

105.9383will be the correct answer hope it helps you