Answer:
A) pbin = 1.535 Kgm/s (+)
B) pbf = 1.696 Kgm/s (-)
C) Δp = 3.3925 Kgm/s
D) Δvr = 10.249 m/s
Explanation:
Given
Mass of the ball: m = 57.5 g = 0.0575 Kg
Initial speed of the ball: vbi = 26.7 m/s
Mass of the racket: M = 331 g = 0.331 Kg
Final speed of the ball: vbf = 29.5 m/s
A) We use the formula
pbin = m*vbi = 0.0575 Kg*26.7 m/s = 1.535 Kgm/s (+)
B) pbf = m*vbf = 0.0575 Kg*29.5 m/s = 1.696 Kgm/s (-)
C) We use the equation
Δp = pbf - pbin = 1.696 Kgm/s - (-1.535 Kgm/s) = 3.3925 Kgm/s
D) Knowing that
Δp = 3.3925 Kgm/s
we can say that
Δp = M*Δvr
⇒ Δvr = Δp / M
⇒ Δvr = 3.3925 Kgm/s / 0.331 Kg
⇒ Δvr = 10.249 m/s
I can not solve the problem if I do not have the mass.
The answer is B, Law of Kinetic Energy
You should select Choice-4 .
