What is the unit of electromotive force?
Joule
Volt
Ampere
Watt
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What is the unit of electromotive force?
Joule
Volt
Ampere
Watt
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The diagram shows two light, silver-coated balls labelled X and Y hanging from threads near to each other.
Which line identifies the possible charges on X and Y?
X | Y | |
A | neutral | neutral |
B | negative | negative |
C | negative | positive |
D | positive | negative |
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Identify the correct unit of charge.
Ampere
Coulomb
Newton
Volt
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Which pair of quantities have the same units?
Current and potential difference
Current and resistance
Electromotive force and potential difference
Electromotive force and resistance
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A PVC (plastic) rod is rubbed with a nylon cloth. This process causes electrons to be transferred between the rod and the cloth, causing both objects to become charged.
Which of the rows in the table below correctly gives the nature of the charges on both the cloth and the rod, and the effect the objects have on each other after becoming charged?
Charges on rod and cloth |
Effect |
|
A |
the same |
repel |
B |
the same |
attract |
C |
opposite |
repel |
D |
opposite |
attract |
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A student wants to charge up some rods by rubbing them with a cloth made from a suitable material.
He has a number of rods to choose from: a copper rod, a PVC rod, an aluminium rod and a glass rod.
Which two of the rods would hold a charge when rubbed with an appropriate cloth?
Aluminium and PVC
Glass and copper
Aluminium and copper
Glass and PVC
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A student muses on the concept of the resistance of a wire.
She wonders whether changing the diameter of the wire and the length of the wire would affect the resistance.
Since you have studied this in physics, you know the answer!
Choose the row from the table in which changes are made to both the diameter and the length that would each decrease the resistance of a wire.
Change to length |
Change to diameter |
|
A |
increase |
increase |
B |
increase |
decrease |
C |
decrease |
increase |
D |
decrease |
decrease |
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A student rubs a polythene rod with a cloth, giving it a negative charge. She then holds it near an earthed, conducting sphere as shown in the diagrams below.
Which of the diagrams shows the correct distribution of charges on the conducting sphere?
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A student has four copper wires, of different dimensions.
Which of her wires has the largest resistance?
Length of wire / cm |
Diameter of wire / mm |
|
A |
100 |
0.2 |
B |
300 |
0.1 |
C |
50 |
0.4 |
D |
30 |
0.5 |
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The diagram shows an uncharged ball covered with metallic paint. The ball is suspended from an insulating thread. It is placed near a positively charged rod.
Which diagram shows the charge distribution on the ball?
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A charge of 45 C flows through an electric appliance in 3.0 minutes.
What is the average current in the appliance?
0.25 A
4.0 A
15 A
135 A
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A wire of length 0.50m and cross-sectional area 1.0 × 10–6m2 has a resistance of 0.75 Ω.
Another wire of the same material has a length of 2.0 m and a cross-sectional area of 0.50 × 10–6m2.
What is the resistance of the longer wire?
0.094 Ω
0.38 Ω
1.5 Ω
6.0 Ω
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Which diagram shows the pattern and direction of the electric field lines near a positive charge?
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A positively charged rod is held close to an insulated metal sphere. The sphere is earthed as shown.
The earth connection is removed and then the rod is removed.
Which diagram shows the charges on the sphere after the rod is removed?
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The diagram shows an electrostatic precipitator. It can be used to remove dust from air.
What happens at the negative grid?
Dust particles gain electrons.
Dust particles gain protons.
Dust particles lose electrons.
Dust particles lose protons.
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What is the definition of an electric field?
A region in space in which a mass experiences a force due to the Earth’s mass.
A region in space through which electromagnetic radiation is passing.
A region in space in which a compass needle experiences a force.
A region in space in which an electric charge experiences a force.
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Four current-voltage graphs are given below.
One of them is for an ohmic resistor, and another is for a filament lamp.
Which is which?
Filament lamp |
Ohmic resistor |
|
A |
Q |
S |
B |
R |
Q |
C |
P |
Q |
D |
Q |
R |
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Which of the diagrams below shows the correct electric field pattern for oppositely charged parallel plates?
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Which row in the table gives the correct units for charge and for EMF?
Charge |
EMF |
|
A |
Q |
E |
B |
C |
V |
C |
A |
J |
D |
J |
ᘯ |
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A student sets up a circuit as shown in the diagram
A charge of 4.9 C flows through the lamp in 0.7 s.
What is the current through the resistor, which direction do electrons flow through the resistor, and what is the direction of the conventional current through the resistor?
Current / A |
Direction of electron flow |
Direction of conventional current |
|
A |
7.00 |
Left to right |
Right to left |
B |
3.43 |
Left to right |
Right to left |
C |
7.00 |
Right to left |
Right to left |
D |
3.43 |
Right to left |
Right to left |
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Which row in the table shows possible values for the two meters shown in the circuit diagram?
X |
Y |
|
A |
4.0 |
8.0 |
B |
2.0 |
2.0 |
C |
4.0 |
2.0 |
D |
1.0 |
1.0 |
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