
Answer:
Given : Â A bus of mass 760 kg requires 120 m to reach certain velocity value Vf.
the bus engine exerts a constant forward force F.
To Find : When the bus is towing a 330-kg small car, how long distance needed to reach same Vf?
Solution:
V²  - U² = 2aS
V = Vf
U = 0
S = 120 m
=> Vf² - 0 = 2a(120)
=> Vf² = 240a
m = 760 Â kg
Force = F
F = ma
=> F =760 a
=> a = F/760
Vf² = 240F/760
Case 2 Â :When the bus is towing a 330-kg small car,
m = 760 + 330 = 1090 kg
a = F/1090
Vf²  = 2aS
=> 240F/760 Â = 2 (F/1090) S
=> S = 120 x 1090 /760
=> S = 172.1 Â m Â
172.1  m  distance needed to reach same Vf
Explanation: