(i) State the principle of dimensional homogeneity of physical equations. (ii) The…

PHYSICS · Subjective · A Level · Physics · Measurements and their errors · Measurements and their errors

Problem

(i) State the principle of dimensional homogeneity of physical equations. (ii) The range R of a projectile projected with an initial speed u at an angle θ to the horizontal is written by a student as R=u sin⁡2θg.R = \frac{u\,\sin 2\theta}{g}. Examine whether this expression is dimensionally consistent. (iii) Another student writes the alternative expression R=u2 sin⁡2θg2.R = \frac{u^{2}\,\sin 2\theta}{g^{2}}. Using dimensional considerations only, explain why this expression cannot be correct.

Related theory

Browse the problem library