Electricity Active Recall QUESTIONS:
1. What is electric current? Flow of positive charge
2. What is the equation for Q=It
charge using current?
3. What is conventional current The flow of charge from positive to negative
defined as?
4. What is current measured Amps
with?
5. How should an ammeter be In series
connected to a circuit?
6. What is potential difference? The energy transferred per unit charge
7. What is potential difference Volts
measured with?
8. How is a voltmeter placed in In parallel with the component being measured
a circuit?
9. What is the definition of The opposition to current.
resistance?
10.What is the equation of R=V/I
resistance using current and
voltage?
11.What does a high resistance Low current. Low resistance, high current
mean for current? And vice
versa?
12.What is ohms law? Given the temperature stays constant, the
current is directly proportional to the voltage
of an ohmic conductor.
13.What equation represents V=IR
ohms law?
14.How can you investigate the Having a circuit with an ammeter, voltmeter,
relation between potential and variable resistor. Adjust resistance and
difference and current across then measure current and voltage to see how
an electrical component? it changes with different resistance
components.
15.What can you see on a graph Straight line through the origin. Constant,
of current against potential positive gradient.
difference or vice versa to
see if a component obeys
ohms law?
16.As potential difference Current, as per ohms law
increase so does what else?
17.For an ohmic conductor like a Straight line through the origin. Constant
resistor, what does the IV gradient.
graph look like?
18.Why does the ohmic Directly proportional, follows ohms law.
conductor graph look that
way?
19.For a semi conductor diode, Horizontal straight line until a positive v point,
what does the IV graph look where it curves upwards.
like?
20.Why does the semi The graph curves upwards when the diode is at
conductor diode graph look a forward bias, so the current and potential
that way? difference can travel through a circuit, when in
reverse bias, the current and potential
, difference cant travel through the circuit,
therefore there is zero current and the line is
horizontal at zero.
21.For a filament lamp, what S shaped looking graph, straight line through
does the IV graph look like? origin for the ohmic region.
22.Why does the filament lamp Follows ohms law, until the lamp heats up and
graph look that way? therefore doesn’t follow ohms law anymore as
this causes the resistance to increase, and the
current stays constant or increases at a slower
rate whilst the potential difference still
increases as the same rate as previously. .
23.Why in terms of electrons, is The electrons collide with the positive ions in
there resistance and heating the wire, and when they collide they transfer
within a wire or component? some or all their energy to ions which causes
electrical heating. Ions resisting the flow of
charges causes an increase in resistance.
24.What is the equation of p=RA/l
resistivity?
25.What is resistivity? The extent as to which a metal opposes the
flow of current through it.
26.What impact does a longer Increase resistance
wire have on resistance?
27.What impact does a thicker Decrease resistance
wire have on resistance?
28.What factor is resistivity Temperature
dependent on?
29.The higher the resistivity of a Resistance
material, the higher the
what?
30.If diameter of a wire doubles, ¼
what factor does the
resistivity increase or
decrease?
31.The higher the temperature, Faster
the slower or faster the
atoms vibrate?
32.Why does current decrease if Resistance increases as the atoms in the wires
a wire gets hotter? vibrate faster and electrons collide with these
vibrating atoms, hence current decreases
33.An increase in temperature Increase
causes what in resistance?
34.For a thermistor, an increase Decrease
in temperature causes what
in resistance?
35.What does a resistance
temperature graph look like?
36.What is the symbol of a Box with hockey stick
thermistor?
37.What are three applications Temperature sensors, fire alarms, ovens,
of a thermistor? refrigerator.
1. What is electric current? Flow of positive charge
2. What is the equation for Q=It
charge using current?
3. What is conventional current The flow of charge from positive to negative
defined as?
4. What is current measured Amps
with?
5. How should an ammeter be In series
connected to a circuit?
6. What is potential difference? The energy transferred per unit charge
7. What is potential difference Volts
measured with?
8. How is a voltmeter placed in In parallel with the component being measured
a circuit?
9. What is the definition of The opposition to current.
resistance?
10.What is the equation of R=V/I
resistance using current and
voltage?
11.What does a high resistance Low current. Low resistance, high current
mean for current? And vice
versa?
12.What is ohms law? Given the temperature stays constant, the
current is directly proportional to the voltage
of an ohmic conductor.
13.What equation represents V=IR
ohms law?
14.How can you investigate the Having a circuit with an ammeter, voltmeter,
relation between potential and variable resistor. Adjust resistance and
difference and current across then measure current and voltage to see how
an electrical component? it changes with different resistance
components.
15.What can you see on a graph Straight line through the origin. Constant,
of current against potential positive gradient.
difference or vice versa to
see if a component obeys
ohms law?
16.As potential difference Current, as per ohms law
increase so does what else?
17.For an ohmic conductor like a Straight line through the origin. Constant
resistor, what does the IV gradient.
graph look like?
18.Why does the ohmic Directly proportional, follows ohms law.
conductor graph look that
way?
19.For a semi conductor diode, Horizontal straight line until a positive v point,
what does the IV graph look where it curves upwards.
like?
20.Why does the semi The graph curves upwards when the diode is at
conductor diode graph look a forward bias, so the current and potential
that way? difference can travel through a circuit, when in
reverse bias, the current and potential
, difference cant travel through the circuit,
therefore there is zero current and the line is
horizontal at zero.
21.For a filament lamp, what S shaped looking graph, straight line through
does the IV graph look like? origin for the ohmic region.
22.Why does the filament lamp Follows ohms law, until the lamp heats up and
graph look that way? therefore doesn’t follow ohms law anymore as
this causes the resistance to increase, and the
current stays constant or increases at a slower
rate whilst the potential difference still
increases as the same rate as previously. .
23.Why in terms of electrons, is The electrons collide with the positive ions in
there resistance and heating the wire, and when they collide they transfer
within a wire or component? some or all their energy to ions which causes
electrical heating. Ions resisting the flow of
charges causes an increase in resistance.
24.What is the equation of p=RA/l
resistivity?
25.What is resistivity? The extent as to which a metal opposes the
flow of current through it.
26.What impact does a longer Increase resistance
wire have on resistance?
27.What impact does a thicker Decrease resistance
wire have on resistance?
28.What factor is resistivity Temperature
dependent on?
29.The higher the resistivity of a Resistance
material, the higher the
what?
30.If diameter of a wire doubles, ¼
what factor does the
resistivity increase or
decrease?
31.The higher the temperature, Faster
the slower or faster the
atoms vibrate?
32.Why does current decrease if Resistance increases as the atoms in the wires
a wire gets hotter? vibrate faster and electrons collide with these
vibrating atoms, hence current decreases
33.An increase in temperature Increase
causes what in resistance?
34.For a thermistor, an increase Decrease
in temperature causes what
in resistance?
35.What does a resistance
temperature graph look like?
36.What is the symbol of a Box with hockey stick
thermistor?
37.What are three applications Temperature sensors, fire alarms, ovens,
of a thermistor? refrigerator.
