Question

A softball, of mass m = 0.195 kg, is pitched at a speed v0 = 25.3 m/s. Due to air resistance, by the time it reaches home plate it has slowed by 11.9%. The distance between the plate and the pitcher is d = 13.7 m. Calculate the average force of air resistance, Fair, that is exerted on the ball during its movement from the pitcher to the plate.

Answer 1

Answer:

$F = 1.0196N$

Explanation:

To give this problem a solution, it is necessary to use the kinematic equations. The equation that describes velocity as a function of acceleration is given by,

$v^2 = v_0^2 -2ax$

Since there is a loss of 11.9%, in the final speed, that is to say that of the total speed, only 88.1% is the effective one, so

$(25.3*88.1\%)^2=25.3^2-2a(13.7)$

Re-arrange to find a,

$a=-\frac{(25.3*88.1\%)^2-25.3^2}{2*13.7}$

$a=5.229m/s^2$

Applying Newton's second law we have now that

$F=ma$

$F = (0.195)(5.229)$

$F = 1.0196N$