(4) there is no unbalanced force on the ball and he 13. An 8000 kg engine pulls a train of 5 wagons, each of 2000 kg along a horizontal track. If 4 a force of 40,000 N and track offers a friction of 5000 N, then net accelerating force actir a is 10,00 11 25. (4) none of th (1) 45,000 N 18) 35,000 N 350 (2) 40,000 N 14. A bullet of mass 25 and by some passes through a board 7.5 cm thick and emere
Answers
Explanation:
Given parameters
Mass of the engine (M) = 8000 kg
Number of wagons = 5
Mass of the wagons (m) = 2000 kg
Force exerted by the engine (F ) = 40000 N
Frictional force offered by the track (Ff) = 5000 N
(a) Net force (Fa) = F – Ff
Fa = 40000 N – 5000 N
Fa = 35000 N
(b) Let us consider the acceleration of the train to be a m/s2
Acceleration is the ratio of net acceleration force by mass, i.e.
a = Fa/m
Where m is the mass of the train, it can be calculated as follows
The total mass of the train (m) = Mass of the engine + (Mass of the wagons × Number of wagons)
m = 8000 + (5 × 2000)
m = 18000 kg
Acceleration of the train (a) = 35000/18000
a = 1.944m/s2
(c) F21 = m4w × a
F21 = Force applied on Wagon 2 by Wagon 1m4w = mass of 4 wagonsa = acceleration of the train
The force of wagon 1 on wagon 2 = Force of wagon 2 on wagon 1
⇒ (4 × 2000 × 1.944)
= 15552 N
∴ The force of wagon-1 on the wagon-2 is 15552 N.