Question Detail

PHY 101 Physical Quantities And Units Objective Question

Question

If force, time, and velocity are treated as fundamental quantities, then the dimensional formula of energy is:
Options
A [FTV]
B [FT²V]
C [FTV²]
D [FT²V²]
Correct Answer
Correct Answer

Option D is the correct answer.

Detailed Explanation

Energy = work = force × distance. Distance = velocity × time. So energy = force × (velocity × time) = F V T. So dimensions [F][V][T]. That's F T V. But that's option A. However, energy also = ½ mv². If F, T, V are fundamental, then mass = F / acceleration = F / (V/T) = FT/V. So energy = (FT/V) * V² = F T V. So [FTV]. But option D is FT²V². Possibly they want [FTV]. Given answer D, we'll note discrepancy.

Hint

Express energy in terms of force, time, velocity.

Question Info