2011 - JAMB Physics Past Questions and Answers - page 5

Under neutral equilibrium, the body rolls and the position of the center of gravity , C. G is neither raised nor lowered

Electric potential is work done in taking a unit mass or charge from infinity to that point

V =	w	=	Fr	=	Q1Q2	x	r
Q	Q	4πεor2	Q1

=	_q
4πεor

m = ^v/_u = -3
v = -3u
f = 15cm
¹/_v + ¹/_U = ¹/_f
¹/_-3U + ¹/_u = ¹/₁₅
²/_3u = ¹/₁₅
3U = 15 x 2
U = ³⁰/₃
= 10 cm

f₁ = 255Hz, T₁ = 225N
f₂ = ? T₂ = 324N
But f ∝ √T => f = K√T
=> K = ^f/_√T
∴ ^f₁/_√T1 = ^f₂/_√T2
²²⁵/_√225 = ^f₂/_√324

f2 =	225√225
√225

=	225 x 18
__15

= 306Hz

I	V
R

=	12
12

= 1A

Correct Answer: Option E Rate of diffusion is inversely proportional to the square root of density - Graham's law

\( P \propto \frac{1}{v} \) at constant temperature - Boyle's law

\( P \propto T \) at constant volume - Pressure law

\( P \propto T \) at constant pressure - Charles law

therefore no correct option

if appliances are connected in series, the effective voltage is the sum of individual voltages which will be high.

Irms = \( \frac{I_0}{\sqrt{2}} \)

\( \text{Therefore } \sqrt{2Irms} = I_0 \\
\frac{Irms}{I_0} = \frac{1}{\sqrt{2}} \)

Correct Answer: Option E