Question

Calculate the force required to impart a bus to a velocity of 20 m/s in 10 seconds starting from the rest. The mass of the bus is 2000 Kg.
1. 6000 N
2. 4000 N
3. 14000 N
4. 10000 N

Answer 1

Correct Answer - Option 2 : 4000 N

The correct answer is 4000 N.

Given

• Mass of the bus = 2000 Kg
• Initial velocity = 0 m/s ( bus starts from rest )
• Final velocity = 20 m/s
• time take = 10 sec

By using equation of motion, 

• v = u + at
• 20 = 0 + a(10)
• a = 20/10 = 2 m/s²
• Now, Force = m × a
• Force= 2000 × 2 = 4000 N