Answer:
98.73 m/s, 83.63 m/s, 87.9 m/s
Explanation:
From the question,
F = m(v-u)/t.............................. Equation 1
Where F = Force, m = mass, v = final velocity, u = initial velocity, t = time.
make u the subject of the equation
u = v-(Ft/m)......................... Equation 2
Given: F = 31 N, m = 11 kg, t = 4 s, v = 110 m/s
Substitute into equation 1
u = 110-(31×4/11)
u = 110-11.27
u = 98.73 m/s.
For, F = -10 N, v = 80 m/s
u = 80-(-10×4/11)
u = 80+3.63
u = 83.63 m/s
For, F = 47 N, v = 105 m/s
u = 105-(47×4/11)
u = 105-17.1
u = 87.9 m/s
The initial velocity at the the beginning of the time interval is 98.73 m/s, 83.63 m/s, 87.9 m/s