Page 541 - SUBSEC October 2017_Neat

UNIT 2
MODULE 1: ELECTRICITY AND MAGNETISM (cont’d)

SPECIFIC OBJECTIVES EXPLANATORY NOTES SUGGESTED PRACTICAL
ACTIVITIES

Electrical Quantities (cont’d)

Students should be able to:

1.6. use the equations
2
2
P = IV, P = I R, P = V /R
to solve problems;

1.7. use the formula Definition of resistivity. Determine the resistance of
ρL wire at varying points and
R = plot a graph of resistance
A
to determine resistivity; versus length.

1.8. use energy considerations Include the observation
to distinguish between that e.m.f. is associated
e.m.f. and p.d.; with sources or active
devices whereas p.d. is used
in reference to an electric
field or passive device.

1.9. explain drift velocity (ν) in
terms of the charge carriers;

1.10. derive the equation
I = nqvA for charges moving
in a metal
(n = charge density); and

1.11. use the equation I = nqvA for Since a similar equation
charges moving in a metal (n describes the flow of
= charge density). particles in uniform
channels, candidates
should be able to apply such
equations to
semiconductors and
electrolytes.

CXC A16/U2/17 41