A cylindrical tube rolling down a slope of inclination θ moves a distance L in time T. The equation relating these quantities is as in the figure. Where a is the internal radius of the tube and P and Q are constants. Which line gives the correct units for P and Q?
B.
D.
C.
A.
Four physical quantities P, Q, R and S are related by the equation PQ²= 8Q + RS. Which statement must be correct for the equation to be homogeneous?
P, Q, R and S are all scalar quantities.
The product PQ² has the same units as Q, and the product RS.
P, Q, R and S all have the same units.
The product PQ² is numerically equal to (8Q+RS).
The magnitude of the force, F, between two masses m1 and m2 separated by a distance r is given by the expression.
F=(Gm1 m2)/r2 The base units for G are
kg³ m³ s⁻².
kgm³ s⁻².
kg⁻¹ m³ s⁻².
kg⁻¹ ms⁻².
