A car's velocity is increasing at the rates of 0.4 ms⁻¹, 0.8 ms⁻¹, 1.2 ms⁻¹ and 1.6 ms⁻¹, one after another. In this case the car is moving with:

Correct answer: d non-uniform acceleration

The rate at which the velocity rises changes each time, 0.4, 0.8, 1.2, 1.6, so the acceleration changes with time. That is non-uniform acceleration.

Why the other options are wrong

• a uniform acceleration: In uniform acceleration the rate at which the velocity rises stays the same each time. Here that rate itself changes, from 0.4 to 0.8, 1.2 and 1.6, so this is not uniform acceleration.
• b uniform momentum: The velocity is rising, so the momentum is rising too and does not stay uniform. The question is about the kind of acceleration.
• c uniform velocity: At uniform velocity the velocity does not change at all and the acceleration is zero. Here the velocity is rising.