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All 9 questions. After you submit, each question shows the right answer and why. Back to the quick check
A battery, a bulb and wires are on a table. What must you make for the bulb to light up?
It is safe to do experiments with the plug sockets in your home as long as you are careful.
Three lamps are wired in series. One lamp breaks. What happens to the other two?
A 6 V battery is connected across a 3 Ω resistor. What current flows, in amperes?
A 12 V lamp draws a current of 2 A. At what rate does it transfer energy, in watts?
A 9 V supply drives a 100 Ω and a 220 Ω resistor connected in series. What current flows, in milliamperes, to one decimal place?
What is the equivalent resistance, in ohms to two decimal places, of a 100 Ω resistor and a 220 Ω resistor connected in parallel?
Using the exact SI value e = 1.602176634 × 10⁻¹⁹ C, how many elementary charges pass a point each second in a current of 2 A? Give the answer in units of 10¹⁸, to two decimal places.
Electrons in a copper wire drift at roughly 10⁻⁴ m/s, yet a lamp several metres away lights almost as soon as the switch closes. Explain the apparent paradox, and say what Ohm's law does and does not tell you about the conductor.
