III: Q2 ELECTRICITY

At constant temperature, the resistance of a conductor changes according to the applied voltage.

• TRUE

• FALSE

The electrical resistance of a wire would be expected to be greater for a longer wire, less for a wire of larger cross sectional area, and would be expected to depend upon the material out of which the wire is made.

• TRUE

• FALSE

Resistance and resistivity are the same.

• TRUE

• FALSE

The resistivity does not depend on the temperature of most metal wires.

• TRUE

• FALSE

While maintaining a constant voltage (V), the current (I) increase when the resistivity ρ of a wire increases.

• TRUE

• FALSE

While maintaining a constant voltage (V), the current (I) decrease when the length (L) of a wire increases.

• TRUE

• FALSE

If the voltage across a circuit of constant resistance is doubled, I will decrease.

• TRUE

• FALSE

The electromotive force is the total voltage induces by the source. In other words, it is the amount of energy supplied by the source to each coulomb of charge.

• TRUE

• FALSE

A shorter wire has more resistance than a shorter wire. Current must travel farther through a longer wire, so there are more chances for it to collide with particles of matter.

• TRUE

• FALSE

A cooler wire has less resistance than a warmer wire. Cooler particles have less kinetic energy, so they move more slowly.

• TRUE

• FALSE