the tennis ball may leave the racquet on the serve with a speed of 65 m/s. If the ball's mass is 60 g, and it is in contact with the racquet for .030 s, what is the average force on the ball?
force*time=mass*changevelocity
solve for force
To find the average force exerted on the ball, we can use Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration (a).
First, we need to find the acceleration of the ball. We know the initial velocity (u) is 0 m/s since the ball is in contact with the racquet before being hit. The final velocity (v) is given as 65 m/s. The time (t) of contact with the racquet is 0.030 s.
To find acceleration (a), we can use the equation v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time.
Rearranging the equation, we have a = (v - u) / t.
Substituting the known values:
a = (65 m/s - 0 m/s) / 0.030 s
a = 2166.67 m/s^2
Now we can calculate the force using Newton's second law. Since the mass is given in grams, we need to convert it to kilograms by dividing by 1000 (1 kg = 1000 g).
m = 60 g / 1000 = 0.06 kg
Using the formula F = ma, we have:
F = 0.06 kg * 2166.67 m/s^2
F = 130 N
Therefore, the average force on the ball is 130 Newtons.