Question

Dave throws a tennis ball straight up into the air. If he throws the ball (with mass 0.07 kg) with a speed of 28 m/s and there is no air resistance, how high does the ball go?

Answer 1

Using the conservation of energy principle, Dave's tennis ball, thrown straight up with a speed of 28 m/s and a mass of 0.07 kg, reaches a height of approximately 39.96 meters when there is no air resistance.

Step-by-step explanation:

Dave throws a tennis ball straight up into the air with a speed of 28 m/s. To find out how high the ball goes, we can use the conservation of energy principle. The initial kinetic energy of the ball is converted to potential energy at its highest point, where its speed is 0 m/s.

The initial kinetic energy (KE) is given by:

KE = (1/2)mv2

Where m is the mass of the ball (0.07 kg) and v is the speed (28 m/s).

The potential energy (PE) at the highest point is given by:

PE = mgh

Where g is the acceleration due to gravity (9.81 m/s2) and h is the height.

Since KE_initial = PE_final, we have:

(1/2)mv2 = mgh

Solving for h, we get:

h = v2 / (2g)

h = (28 m/s)2 / (2 * 9.81 m/s2)

h = 784 / 19.62 m

h ≈ 39.96 m

Therefore, the ball reaches a height of approximately 39.96 meters.