#100.
Which of the following are characteristics of a series circuit?
I. The current that flows through each resistance is the same as the total current throughout the
circuit.
II. The sum of all the individual voltage drops is the same as the applied voltage.
III. The reciprocal of the total resistance is equal to the sum of the reciprocals of the separate
resistances.
IV. The voltage drop in each resistance is the same as the magnitude of the applied voltage.
A
III and IV
B
I and III
C
I and II
D
I, II and III
Answer: I and II
#101.
Which states that the sum of all potential rises and potential drops in any loop (closed circuit) is
zero?
A
Coulomb's Law
B
Law of Electrolysis
C
Kirchoff's Law
D
Ohm's Law
Answer: Kirchoff's Law
#102.
A television and an electric fan are connected in parallel top a 220 V line. The current in the
television is 8 A and in the electric fan is 3 A. What is the current flowing in the line?
A
11 A
B
24 A
C
5 A
D
2.67 A
Answer: 11 A
#103.
What happens to current if resistance increases?
A
Increases
B
Decreases
C
No change
D
Cannot be determined
Answer: Decreases
#104.
Which of the following statements DOES NOT represent Ohm's Law?
A
current = resistance x potential difference
B
current/potential difference = constant
C
potential difference/current = constant
D
potential difference = current x resistance
Answer: current = resistance x potential difference
#105.
What is the resistance of an electric bulb drawing 1.2 A current and 6.0 V?
A
0.2 ohm
B
0.5 ohm
C
5 ohm
D
2 ohm
Answer: 5 ohm
#106.
What happens to the current-carrying ability of a wire as temperature increases?
A
The wire can't carry any current.
B
The wire can carry more current.
C
The wire can carry less current.
D
There is no change.
Answer: The wire can carry less current.
#107.
A 300 W at 220 V TV set is used at an average of 4 hours a day for 30 days. If the electrical
energy costs P1.60 per kilowatt-hour, how much is the energy cost?
A
P5.76
B
P225.00
C
P57.60
D
P22.50
Answer: P57.60
#108.
Electromagnetic radiation can be used for wireless communications. Which of the following can
be used to transmit signals such as mobile phone calls?
A
Infrared
B
Microwaves
C
Gamma
D
Radio waves
Answer: Microwaves
#109.
Which statement about the North-magnetic pole of the Earth is TRUE?
A
It corresponds to the N-pole of a bar magnet.
B
It corresponds to the S-pole of a bar magnet.
C
Its location never changes.
D
It is at the same location as the geographic north pole of the Earth.
Answer: It corresponds to the S-pole of a bar magnet.
#110.
An iron nail can be turned into a temporary magnet if it is held in a strong magnetic field. Which
method of magnetization is this?
A
Charging
B
Conduction
C
Induction
D
Saturation
Answer: Induction
#111.
Which of the following factors affect the size of the induced current in a coil?
I. Number of turns in the coil
II. Size of the inducing field
III. Direction of the windings in the coil
IV. Resistance of the wire in the coil
A
I, II and III
B
III and IV
C
I, II and IV
D
I and II
Answer: I, II and IV
#112.
To use the right hand rule to predict the direction of an induced current in a coil, your thumb
must point ________.
A
to the direction of the motion of the wire
B
in the direction of the inducing field
C
to the N-pole of the induced magnetic field
D
in the direction of the induced current
Answer: to the N-pole of the induced magnetic field
#113.
When a bar magnet is inserted into a coil, a current of 12.0 A is induced into the coil. If four
magnets of the same type are inserted into the coil at the same time, what would be the induced
current?
A
12 A
B
4 A
C
3 A
D
48 A
Answer: 48 A
#114.
What is the direction of a magnetic field within a magnet?
A
from to back
B
from north to south
C
from south to north
D
back to front
Answer: from north to south
#115.
Which is the induced voltage across a stationary conductor in a stationary magnetic field?
A
reversed in polarity
B
increased
C
zero
D
decreased
Answer: zero
#116.
What is the magnetomotive force (mmf) of a wire with 8 turns carrying 3 A of current?
A
2,400
B
240
C
24
D
2.67
Answer: 24
#117.
A coil of wire is placed in a changing magnetic field. If the number of turns in the coil is
decreased, what will happen to the voltage induced across the coil?
A
remain constant
B
deceased
C
be excessive
D
increased
Answer: deceased
#118.
Which of the following is TRUE about the frequency and velocity of electromagnetic waves?
A
As frequency increases, wavelength increases
B
As frequency increases, wavelength decreases
C
Frequency is constant for all wavelengths
D
Frequency and wavelength are interdependent of each other
Answer: As frequency increases, wavelength decreases
#119.
Which of the following correctly lists electromagnetic waves in order from longest to shortest
wavelength?
A
microwaves, ultraviolet, visible light, gamma rays