4.3. Electric circuits
A subsection of Physics, 5054, through 4. Electricity and magnetism
Listing 10 of 85 questions
A student connects a battery to two resistors. The circuit diagram is shown in . 10 Ω 40 Ω The potential difference (p.d.) across the 40 Ω resistor is 9.6 V. State what is meant by the potential difference across a resistor. Calculate the current in the 40 Ω resistor. current = Calculate the electromotive force (e.m.f.) of the battery. e.m.f. = The student has three different voltmeters to measure the p.d. across the 40 Ω resistor. These are labelled 0–2 V, 0–20 V and 0–200 V. Each has a pointer that shows the p.d. on a scale. State and explain which of the three voltmeters is best to measure this p.d. Calculate the power P produced in the 10 Ω resistor. P = The student has available two 10 Ω resistors, with power ratings of 2 1P and 2P. Suggest why a resistor with a power rating of 2 1P is not suitable for the circuit in . The student adds a resistor R to the circuit, to make the circuit shown in . 10 Ω R Ω Complete the table in to show what happens as resistor R is connected. You should state whether each quantity increases, decreases or stays the same and give a brief explanation of why any change occurs. Calculations are not required. quantity increases, decreases or stays the same as resistor R is added brief explanation of why the change occurs current in 10 Ω resistor increases p.d. across 10 Ω resistor p.d. across 40 Ω resistor
5054_s18_qp_22
THEORY
2018
Paper 2, Variant 2
View
shows a circuit containing three resistors, a 12 V power supply and an ammeter. 400 Ω 200 Ω 100 Ω A 12 V + – Calculate the current in the 400 Ω resistor. current = A Calculate the power produced in the 400 Ω resistor. power = W A student uses all of the components shown in in another circuit. She connects them so that there is the largest possible current in each resistor. The current in one of the resistors is larger than the current in the other two resistors. The student connects the ammeter into the circuit to measure the current in this resistor. Draw the circuit diagram of the arrangement. Label each resistor with the value of its resistance.
5054_s23_qp_21
THEORY
2023
Paper 2, Variant 1
View
Questions Discovered
85