OAR OAR Mechanical Comprehension: Electricity 4

Question 1

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

Accepted Answer

The 60W bulb

Answer

In series, the same current flows through both; the 60W bulb has higher resistance and dissipates more power (P = I²R).

Question 2

What is the relationship between frequency and period of an AC waveform?

Accepted Answer

f = 1/T

Answer

Frequency and period are reciprocals: f = 1/T, where T is the time for one complete cycle.

Question 3

What happens to resistance as the temperature of a metal conductor increases?

Accepted Answer

Resistance increases

Answer

In metals, higher temperature increases atomic vibration, impeding electron flow and raising resistance.

Question 4

A 12V circuit draws 3A. A second identical load is added in parallel. What is the new total current?

Accepted Answer

6A

Answer

Each parallel branch draws 3A, so total current doubles to 6A with two identical loads.

Question 5

What is the standard frequency of AC power in the United States?

Accepted Answer

60 Hz

Answer

US power grids operate at 60 Hz, meaning alternating current completes 60 cycles per second.

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