EOC 8 test

What is the e.m.f. of a cell?

• the amount of charge that passes through the cell per unit time.

• the energy gained per unit charge as charge passes through the cell

• the total amount of charge flowing through the cell

• the total energy stored in the cell

A student measures the p.d. across a device and the current in the device.

Which calculation gives the resistance of the device?

• current + p.d.

• current : p.d.

• p.d. : current

• p.d. x current

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

There is a current in a variable resistor when a potential p.d. is applied across it. In which situation is the current increased?

• Decrease the p.d. and keep the resistance the same

• Decrease the p.d. and increase the resistance

• Keep the p.d. the same and decrease the resistance

• Keep the p.d. the same and increase the resistance

• A

• B

• C

• D

A negatively charged plastic rod is brought near to an uncharged metal sphere and held there.

What happens when the metal sphere is earthed?

• electrons flow from the metal sphere to earth

• electrons flow from earth to the metal sphere

• positive charge flows from the metal sphere to earth

• positive charge flows from earth to the metal sphere

Four wires are made of the same metal.

Which wire has the greatest resistance?

• a 100 cm long wire with a diameter of 3.0 mm

• a 100 cm long wire with a diameter of 6.0 mm

• a 10 cm long wire with a diameter of 3.0 mm

• a 10 cm long wire with a diameter of 6.0 mm

• A

• B

• C

• D