An object of mass 2kg moves for 5s with a uniform velocity of 10ms. What is the magnitude of its acceleration in $ms^{-2}$ ?

Analyze the question: The object moves with a uniform velocity of 10 m/s. The mass (2 kg) and time (5 s) are extra details that don't change the result.

Concept: Acceleration is the rate of change of velocity:

Uniform velocity means the velocity is constant, so it does not change with time. Constant velocity means no change in speed and no change in direction.

Solution:

• Initial velocity, u = 10 m/s
• Final velocity, v = 10 m/s (unchanged, since it is uniform)
• Time, t = 5 s

This also agrees with Newton's first law. If there is no acceleration, the net force on the object is zero (F = ma = 2 × 0 = 0 N), so it keeps moving at constant velocity.

Checking the other options: Some of the distractors come from misusing the numbers. For example, 10 ÷ 5 × ... or 10 × 5 / 2 = 25 (not listed), and 10/2 = 5 (not listed). Options like 2.5, 12.5 and 100 come from mixing the given values in formulas that don't apply here.

Answer: A. zero

Tip: In exam questions, the phrases "uniform velocity" or "constant velocity" almost always mean acceleration = 0. Don't be distracted by extra data such as mass and time. If you see "uniform acceleration," that is different, because then the velocity changes steadily.