The diagram shows an arrangement of resistors. What is the total electrical resistance between X and Y?
Less than 1 ohm.
40 ohms.
Between 10 ohms and 30 ohms.
7.5 ohms.
Electrons drift through a section of a piece of copper wire containing 1029 electrons per unit volume with a velocity of 2.9 × 10⁻⁴ m/s.
The current density through the wire is:
4.6 × 10⁶ A/m².
2.9 × 1025 A/m².
4.6 × 1013 A/m².
5.5 × 1013 A/m².
What is the potential of point D relative to point C in in the circuit below?
+6.0 V.
+2.0 V.
+4.0 V.
+3.0 V.
What current flows in the 12 ohms resistor in the circuit below:
0.50 A.
1.0 A.
0.25 A.
0.75 A.
