2003 - JAMB Physics Past Questions and Answers - page 1

K = 500Nm^-1; M = 5 x 10^-3kg; e = 0.02m;

g = 10ms^-2. The elastic potential energy stored in the compressed spring is given by = ¹/₂Ke², and the energy is transformed into gravitational potential energy = mgh, thus from the principle of energy conversion, we have that mgh = ¹/₂Ke²

5 x 10^-3 x 10 x h = ¹/₂ x 500 x (0.02)²

∴ h = 1 x 500 x 0.02 x 0.022 x 5 x 10^-3 x 10

= 5 x 2 x 0.02___10^-1

= 10 x 0.02 x 10 = 2

∴ h = 2m

Pressure = ^F/_A = pgh, where p = density, h = depth and g = 10ms^-2

But F = P x A

∴ Force exerted by the load test tube = cross-sectional Area x Pressure

i.e F = A x pgh

= 0.028m or 2.8m

Vol = cross-sectional area x length

∴ vol. of water disharged per sec

= 60ms^-1 x 0.5m

= 30m³ 5^-1

=> Vol. of water discharged in the said 20s

= 30m³ x 20 = 600m³

∴ vol. of the container = 600m³

A body sliding down a plane inclined at 30^o to the horizontal, has coefficient of friction

= tan 30^o = ¹/_√3

Surface tension - The tendency of a liquid surface to behave as an elastic skin

Pressure P = ^F/_A

= ^F/_πr²

AS the stone is whirled round and te string suddenly cuts, say at A, B, C or D. The stone will fly off in the direction indicated V_A, V_B, V_C or V_D respectively which is tangential to the circular path

Since the lever is a uniform one, its center of gravity will be acting half way (i.e 45cm)

∴from the principle of moments,

F x 45 = 30 x 30

∴ F = (30 x 30) / 45 = 20N

A satellite is said to be in a parking orbit if its period is exactly equal to the period of the earth as it turns its own orbit;. which is about 24hrs