Question

A ball is thrown 10-m straight up from an initial height 2-m above the ground.

1 .Calculate how fats the ball was thrown ?
2 .Calculate the time in the air to reaching the maximum height ?

Answer 1

To calculate how fast the ball was thrown, use the equation v = u + gt, where v is the final velocity, u is the initial velocity, g is the acceleration due to gravity, and t is the time taken. To calculate the time in the air to reach the maximum height, use the equation t = (v - u) / g.

Step-by-step explanation:

(a) To calculate how fast the ball was thrown, we need to first determine the time it takes for the ball to reach its maximum height. We can use the equation:

v = u + gt

Where:

• v is the final velocity (0 m/s at maximum height)
• u is the initial velocity (what we are trying to find)
• g is the acceleration due to gravity (-9.8 m/s^2)
• t is the time taken to reach the maximum height

Substituting the values, we have:

0 = u - 9.8t

Solving for u, we get:

u = 9.8t

(b) To calculate the time in the air to reach the maximum height, we can use the equation:

t = (v - u) / g

Where:

• t is the time taken (what we are trying to find)
• v is the final velocity (0 m/s at maximum height)
• u is the initial velocity (9.8t, as calculated in part a)
• g is the acceleration due to gravity (-9.8 m/s^2)

Substituting the values, we have:

t = (0 - 9.8t) / -9.8

Simplifying the equation, we get:

t^2 = 2t

t = 0 or t = 2

Since time cannot be negative, the ball takes 2 seconds to reach the maximum height.