Explanation:
Only option (1) shows a Wheatstone bridge configuration for balance.
26
A sheet near a strong magnetic pole requires force to: A: Hold if magnetic. B: Hold if non-magnetic. C: Move if conducting. D: Move if non-conducting/non-polar. Correct statement(s):
Correct Answer:B
Explanation:
Force is needed to hold magnetic material (A) and to move conducting sheet (C) due to eddy currents.
27
When parallel plate capacitor plates are moved closer: A: Charge increases. B: Energy decreases. C: Capacitance increases. D: Q/V remains same. E: QV increases. Correct option:
Correct Answer:B
Explanation:
Capacitance \(C ∝ \frac{1}{d}\) increases, but Q/V (capacitance) remains same if connected to battery (D). QV increases as Q increases (E).
28
Two heaters (1 kW and 2 kW) connected in series then parallel. The power output ratio (series : parallel) is:
Correct Answer:B
Explanation:
Series: \(P_{series} = \frac{V^2}{R_1 + R_2}\). Parallel: \(P_{parallel} = \frac{V^2}{R_1} + \frac{V^2}{R_2}\). Ratio calculates to 2:9.