Electricity Review

What could not be used to create an electric current?

• alpha-particles 

  
  

• beta-particles 

• neutrons 

• protons

A fine mist of oil droplets is sprayed into air. As the oil droplets leave the nozzle of the spraying device they can become electrically charged. What is not a possible value for the charge on an oil droplet?

• zero

• 1.0 x 10^-19 C

• 4.8 x 10^-19 C

• 8.0 x 10^-19 C

An electric current is formed by moving charge carriers. What is not a possible charge on a charge carrier?

• • -4.8 x 10^-19 C

• -2.4 x 10^-19 C

• 1.6 x 10^-19 C

• 3.2 x 10^-19 C

Calculate the current in a circuit when a charge of 180 C passes a point in a circuit in 2.0 minutes.

• 1.0 A

• 1.5 A

• 90 A

• 360 A

There is a current of 10 A through a lamp for 1.0 hour. Calculate how much charge flows through the lamp in this time

• 3.6 x 10⁴ C

• 2.4 x 10⁴ C

• 1.2 x 10⁴ C

• 0.6 x 10⁴ C

Calculate the number of protons that would have a charge of one coulomb. (Proton charge = +1.6 × 10⁻¹⁹ C.)

• 6 x 10¹⁸

• 8 x 10¹⁸

• 9 x 10¹⁸

• 12 x 10¹⁸

Calculate the number of electrons that would have a charge of one coulomb. (Electron charge = -1.6 × 10⁻¹⁹ C.)

• 6 x 10¹⁸

• 8 x 10¹⁸

• 9 x 10¹⁸

• 12 x 10¹⁸

The electric current in a metal wire is 4.0 mA. How many electrons pass a fixed point in the wire in a time of 10 hours?

• 2.5 x 10¹⁷

• 2.5 x 10²⁰

• 9.0 x 10²⁰

• 9.0 x 10²³

What is the definition of the potential difference (p.d.) across a component?

• the energy transferred per unit charge

• the energy transferred per unit current

• the power transferred per unit charge

• the power transferred per unit current

Which quantity is given by the product of charge and electric potential difference?

• current

• energy transferred

• power dissipated

• resistance