MCQs on Static Electricity
Ques 1. Electric current originates from which part of an atom?
a. Nucleus
b. Entire atom acting as a unit
c. Positively charged protons
d. Negatively charged electrons
Ques 2. Which of the following is true of electrical forces?
a. Like charges attract, unlike charges repel.
b. Electrical forces are produced by electrical charges.
c. Positive and negative charges can combine to produce the third
type.
d. Electrical forces are weaker than gravitational forces.
Ques 3. When a person combs her hair, static electricity is sometimes
generated by what process?
a. Friction between the comb and hair transfers electrons.
b. Induction between the comb and hair.
c. Deduction between the comb and hair.
d. Contact between the comb and hair results in a charge.
Ques 4. Attraction is the actual proof of an object being charged.
a. True
b. False
Ques 5. If an object is positively charged, theoretically the mass of the
object ______
a. Increases slightly by a factor of 9.11*10-31 kg
b. Decreases slightly by a factor of 9.11*10-31 kg
c. Remains the same
d. May increase or decrease
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Ques 6. Why is gold used in the Gold-leaf electroscope?
a. Gold is easily available in nature
b. Gold is malleable
c. Gold is conducting in nature
d. Gold is cheap
Ques 7. What happens to the plates of the apparatus if we measure
alternating charge using a Gold-leaf oscilloscope?
a. It doesn’t diverge at all
b. It diverges momentarily
c. The plates give a proper divergence
d. The degree of divergence increases and decreases repeatedly
Ques 8. Why can’t we induce static electricity in a brass road by friction if
we hold it in out hand?
a. Static electricity is induced only on insulators while brass is
conducting
b. The induced static charge will flow through our body to the ground
c. The static charge was not produced at all
d. It is not possible to induce static electricity by friction
Ques 9. A gold-leaf electroscope is used for?
a. Only to detect the presence of charge
b. To detect the presence of charge as well as its nature (positive or
negative)
c. To measure the surface charge density
d. To measure current
Ques 10. 1 Coulomb = ________ Electro Static Unit.
a. 3*109
b. 3*108
c. 1.602*10-19
d. 2*109
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Ques 11. Number of electrons in 1 Coulomb charge is _________
a. 6.25 * 1021
b. 6.25 * 1020
c. 6.25 * 1025
d. 6.25 * 1023
Ques 12. What happens if two equally and oppositely charged spheres
touch each other?
a. Attract each other with the same amount of force
b. Repel each other
c. Attract each other with less amount of force
d. Don’t attract or repel
Ques 13. Which among the following cannot be the charge of a charged
body?
a. 4.8 * 10-14 Coulomb
b. 6.4 * 10-15 Coulomb
c. 5 * 10-14 Coulomb
d. 3.2 * 10-10 Coulomb
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CIRCUIT DIAGRAMS
1. Two cell battery connected to three light bulbs in series.
2. One battery connected to two light bulbs in parallel. One light bulb is controlled by a
switch.
3. Two one-celled batteries in parallel, connected to three light bulbs in series. The bulbs are controlled by a
switch.
4. Three celled battery connected to two light bulbs in parallel and a third light bulb connected in series.
5. A one celled battery, a switch that controls the entire circuit, a motor and a light bulb. The motor must
continue to work, if the light bulb burns out.
6. Four bulbs are connected in series to a three celled battery with a switch and a properly placed fuse.
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7. Two bulbs in parallel and a third in series are connected to a two cell battery and a switch that works on the
second bulb only.
8. Draw a series connection of a cell, a switch, and a bulb. Show the voltmeter connected to measure the
electrical potential of the source and an ammeter connected to measure the electric current in the circuit.
9. Three 3V cells connected in series, a switch, an ammeter for measuring the total current coming from the
cell, three light bulbs connected in parallel and a voltmeter for measuring the potential difference across the
second light bulb. The switch should control all three light bulbs at once. Label all positive and negative
terminals.
10. Four bulbs in all, two in parallel to each other placed between two in series, all connected to a three cell
battery. A switch, a fuse, an ammeter before the first light bulb and a voltmeter across the source.
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Quantities in Series & Parallel
Section 13.10: How Series & Parallel Circuits Differ
1. Compare the total resistance of loads connected in series with those loads connected in parallel.
2. Why is it a bad idea to connect too many devices in parallel to an energy source, such as a wall outlet?
3.
a) What would happen to the voltage drop across each lamp if you kept adding lamps to a series circuit?
b) What do you think you would observe in terms of the brightness of the lamps?
4. Use the diagram below to answer the questions that follow:
a) What will happen to the other lamps if lamp 1 is unscrewed?
b) What will happen to the other lamps is lamp 4 is unscrewed?
5. Use your knowledge of circuits in series & parallel to fill in the missing values in the diagrams below:
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Name: _______________________________
VOLTAGE, CURRENT AND RESISTANCE Worksheet
resistance = potential difference
current
R=V
I
Units: R is measured in ohms (Ω)
V is measured in volts (V)
I is measured in amperes (A)
1. Solve for the unknown measurement.
a) I = 10 A
R = 1500 Ω
V=?
b) I = ?
R = 200 Ω
V = 240 V
c) I = 15 A
R=?
V = 110 V
2. Find the unknown quantity (CONVERT to the base unit FIRST, then solve).
a) I = ?
b) R = ?
R = 20 Ω
I = 25 mA = _________ A
V = 350 mV = ________ V
V = 110 V
c) I = 15 A
R = 7333 mΩ = _______ Ω
V=?
WORD PROBLEMS → Be sure to check your units before solving the following questions!
3. How much resistance does a light bulb create if it has a current of 25 mA around it in a 9 V circuit?
I = 25 mA =
V=
R=?
4. How much current flows through a 16 V battery that has a resistance of 5.1 Ω?
5. The human body offers a very small amount of resistance (let’s say 1 mΩ for argument). If a lightning bolt
(said to have 1.21 GV of potential according to a famous movie called Back to the Future released in 1984)
hits you, how much current is flowing through your body? PS. It takes a mere 50 mA of current to kill a
human being.
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Resistance and Ohm’s Law
Complete the following questions using the equation:
V=IxR
or
R=V÷I
or
I=V÷ R
6. What is the potential difference across an electrical load that has a resistance of 4 Ω and a current of 3 A
flowing through it?
7. Calculate the current an electric clothes dryer draws when it is connected to a 230 V source ands has a resistance
of 9.2 Ω.
8. What is the resistance in a circuit if a potential difference of 110 V causes a current of 10 A?
9. What is the potential difference across a hand-held fan that has a resistance of 120 Ω and a current of 50 mA
flowing through it?
10. An electric toaster has a resistance of 12 Ω. What current will it draw from a 120 V supply?
11. a) A portable radio connected to a 9.0 V battery draws a current of 25 A. What is the resistance of the radio?
b) What type of energy is the electrical energy from the battery being converted into in this device?
12. A heating coil offers a resistance of 2.5 kΩ. What potential difference is required so that 1.5 A of current pass
through it?
13. How much resistance does a heavy duty flashlight have if it has a current of 25 mA flowing through it and is being
powered by four 1.5 V cells?
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Answer Key:
1a. 15000V
1b. 1.2A
1c. 7.33Ω
2a. 0.175A
2b. 4400 Ω
2c. 109.995V
3. 360 Ω
4. 3.14A
5. 1.21x1021A
6. 12V
7. 25A
8. 11 Ω
9. 6V
10. 10A
11a. 0.36 Ω
11b. sound and heat
12. 3750V
13. Vtot = 6V, 0.15 Ω
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