WorksheetsElectronics KSSM
Total questions: 10
Worksheet time: 5mins
P
Q
R
S
the resistor R is disconnected
the surrounding is bright
the terminals of the battery are reversed
the surrounding is dark
A thermistor and a transistor are connected in a fire alarm circuit. The resistance of the thermistor decreases as the temperature rises.
Which of the following circuits will cause the bell to ring when there is a fire?
A light-dependent resistor (LDR) is a resistor which is sensitive to light. The resistance of the LDR is low when surrounding is bright and high in the dark.
Which circuit will light up the bulb at night?
What electronic component allows current to flow in one direction only?
Resistor
LED
Diode
Switch
Doping is a process of adding a certain amount of specific impurities to semiconductor. What is the purpose of doping?
To increase the resistance of semiconductor
To increase the thermal energy of semiconductor
To increase the temperature of the semiconductor
To increase the conductivity of the semiconductor
Thermionic emission involves
the release of electron from the surface of the heated metal.
the deflection of an electron beam by the Y-plate.
the forming of a bright spot when the electrons strike the fluorescent screen.
the ionization of the surrounding air by heat.
Diagram shows a cathode ray tube. If electrons are accelerated from cathode from rest, find the maximum velocity of
the electrons on reaching the anode.
(Mass of an electron = 9.1×10−31 kg ; charge of an electron = 1.6×10−19 C )
2.96×107 m s−1
4.40×107 m s−1
0.75×1015 m s−1
1.50×1015 m s−1
Diagram shows four diodes connected to a direct current power supply, d.c
Which diodes are connected in forward bias?
W and Y
W and Z
X and Y
X and Z
Which of the following is not the property of cathode ray?
It travels in a straight line
It is not affected by gravity
It has momentum and energy
It can be deflected in electric field
