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WorksheetsElectric circuits DBE grade 12 Part 1
Total questions: 34
Worksheet time: 2hrs 54mins
Which ONE of the circuits below can be used to measure the current in conductor X and the potential difference across its ends?
Ampere second could be the unit of
power
energy
conductance
charge
A circuit contains two unequal resistances in parallel; therefore:
The current is the same in both.
A larger current flows in the larger resistor
The potential difference across each resistor is the same
The smaller resistance has a smaller current flowing through it
Three equal resistors connected in a series across a source of emf together dissipate10 watts of power. What would be the power dissipated in the same resistors if they are connected in parallel across the same source of emf?
10 watts
30 watts
90 watts
270 watts
Five resistances are connected as shown below, and the combination is connected to a 40 V supply. What is the voltage between P and Q?
40 V
20 V
22,5 V
17,5 V
The current intensity in the circuit is 0,8 A and the voltage on the resistor is 20 V. What is the electrical power of this circuit?
0.04 W
16 kW
16 W
25 kW
Which of the following statements is true?
Internal resistance mainly affects low-current loads
Internal resistance mainly affects low-resistance loads
Internal resistance mainly affects high-resistance loads
Which of the diagrams below represents a circuit in which the following 2 situations are possible?
When Switch S1 is on and Switch S2 is off, only light L1 will be on.
When Switch S1 is off and Switch S2 is on, neither light will be on.
The current I in the figure is
1,5 A
0,5 A
3,5 A
2,5 A
The circuit diagram contains a combination of resistors R1, R2 and R3. The battery has an emf of 12 V and an unknown resistor (R).
When switch S is closed:
Rexternal-decreases &
Reading on ammeter A-
increases
Rexternal-decreases &
Reading on ammeter A-
remains constant
Rexternal-decreases &
Reading on ammeter A-
decreases
Rexternal-increases &
Reading on ammeter A-
increases
*Do not write symbols just answers
*Keep your answer for other questions
Calculate the reading on A1
(a)
*Do not write symbols just answers
*Keep your answer for other questions
Calculate the total resistance of the circuit
(a)
*Do not write symbols just answers
*Keep your answer for other questions
Calculate the total resistance of R to 2 decimal places
(a)
*Do not write symbols just answers
*Keep your answer for other questions
Calculate the total resistance of R to 2 decimal places
(a)
With an open switch determine the reading on A1
(a)
With an open switch determine the reading on voltmeter V
(a)
Calculate the resistance of metal wire at T1
(a)
Calculate the power dissipated in the metal wire when the current strength in it is 25 mA at temperature T2
to 3 decimal places
(a)
Determine the potential difference across the
0,4Ω resistor to one decimal place
(a)
Determine the reading on voltmeter the to one decimal place V2
(a)
Determine the current strength through ammeter A2
(a)
Calculate the internal resistance of the battery correct to 2 decimal places
(a)
Calculate the effective resistance of the parallel combination correct to 1 decimal place
(a)
With the switch open calculate the reading on the ammeter
(a)
Calculate the current strength in the 100Ω resistor correct to 2 decimal places
(a)
Calculate the reading of voltmeter V2 resistor correct to 2 decimal places
(a)
Calculate the reading of voltmeter V1 resistor correct to 2 decimal places
(a)
Calculate the emf of the battery to 1 decimal places
(a)
Thembi wants to listen to her radio which is rated 6V , 3W. The only available battery is a 24 V battery. She decides to use an appropriate resistor to get the correct voltage for her radio.
Calculate the maximum strength the radio draws from the battery when operating at its rated voltage correct to 1 decimal place
(a)
Thembi wants to listen to her radio which is rated 6V , 3W. The only available battery is a 24 V battery. She decides to use an appropriate resistor to get the correct voltage for her radio.
If the battery has internal resistance of 2Ω , calculate the resistance of the resistor which Thembi has to use
(a)
The element of an electric cattle is rated at 1320 W when operating at 220 V supply. Calculate the total charge passing through the element in 10 minutes of operation
(a)
A light bulb that is marked 100 W is used in your room as a light source potential difference of 220 V across the bulb ensures a work rate (power) of 100 W
Calculate the amount of charge that passes the light bulb per second correct to 2 decimal places
(a)
A light bulb that is marked 100 W is used in your room as a light source potential difference of 220 V across the bulb ensures a work rate (power) of 100 W
Determine the resistance of the filament in the light bulb
(a)
A light bulb that is marked 100 W is used in your room as a light source potential difference of 220 V across the bulb ensures a work rate (power) of 100 W
Calculate the magnitude of the electrical current that flows through the light bulb correct to 2 decimal places
(a)
