JEE Physics - MCQ Practice Questions

In a potentiometer experiment, the balancing length for a cell of EMF E is 75 cm. If another cell of EMF E/2 is used, the balancing length would be:

A meter bridge is balanced when the jockey is at 40 cm mark. If the known resistance is 12Ω, the unknown resistance is:

The EMF of a cell is 2V and its internal resistance is 0.5Ω. When connected to external resistance, the terminal voltage is 1.8V. The current in the circuit is:

When a conductor is heated, its resistance increases because:

A copper wire and an aluminum wire of same length and cross-sectional area carry the same current. Which has greater voltage drop?

Two resistors of 4Ω and 6Ω are connected in series with a 10V battery. The current through the circuit and power dissipated are respectively:

A wire of length L and cross-sectional area A has resistivity ρ. If the wire is stretched to double its length, what will be the new resistance?

A battery with EMF E and internal resistance r is connected to an external resistance R. What is the terminal voltage?

A potentiometer wire of length 100 cm has resistance 10Ω. A standard cell of EMF 1.5V is balanced at 40 cm. What is the EMF of an unknown cell if balanced at 65 cm?

In a circuit, the current through a 10Ω resistor is 2A. If this resistor is replaced by 5Ω, and the rest of the circuit remains unchanged, the new current will be:

A uniform wire of length L is cut into n equal parts. When connected in parallel, the equivalent resistance is:

If the length of a conductor is doubled and the diameter is also doubled, what happens to its resistance?

A 60W bulb and a 100W bulb are connected in series across a 200V supply. Which bulb glows brighter?

An ammeter has a low resistance and a voltmeter has a high resistance. This is because:

Three cells of EMF 2V, 4V, and 3V with negligible internal resistance are connected in series, opposing each other. Net EMF is:

A 100Ω resistor and a 200Ω resistor are connected in parallel, and this combination is in series with a 50Ω resistor. Total resistance is:

A wire of length L and cross-sectional area A has resistivity ρ. If the wire is stretched to 2L without change in volume, what will be its new resistance?

In a Wheatstone bridge, if P/Q = R/S, then the current through the galvanometer is:

A cell of EMF E and internal resistance r is connected to an external resistance R. The terminal voltage V is given by:

A potentiometer wire of length 100 cm has resistance 10Ω. A standard cell of EMF 1.5V is balanced at 60 cm. What is the EMF of unknown cell if it balances at 80 cm?