Electricity calculations (V=IR, P=IV, Q=It)

what is the power of a lamp whose current is 6 A and the voltage across it is 120 V?

• 120 W
• 720 W
• 16 W
• 10 W

Which are the Equations for Power?

• Power = Energy Transferred / Time (P=E/t)

• Power = Work Done / Time (P=W/t)

• Power = Energy Transferred x Time (P=Et)

• Power = Work Done x Time (P=Wt)

What is the Equation for Charge Flow?

• Charge Flow = Current x Time (Q=It)

• Charge Flow = Current / Time (Q=I/t)

• Charge Flow = Time / Current (Q=t/I)

Potential difference (pd) / voltage equation

• V= IR

How much charge flows through a wire in 80s if the current is a constant 5.4A?

• 432C

• 360C

• 524C

• 344C

If the current through a circuit is 2 A and the resistance of a light bulb in the circuit is 10 Ohms, what is the voltage difference across the light bulb?

• 5 V
• 12 V
• 0.2 V
• 20 V

A correct statement of Ohm’s Law is:

• I= V R
• V ∝ I
• V = IR
• both b and c

How many volts are in a circuit with a battery that has a resistance of 10 Ohms and a current of 2 Amps? 

• .5 Volts
• 5 Volts
• 20 Volts

Calculate the power rating of an electric toaster that uses 210 000 J while toasting bread for 140 s

• 1500 J

• 1200 W

• 1500 W

• 1300 J

What is the Voltage of a circuit that has a resistance of 5 Ω and a current of 2 A?

• 25 V
• 10 V
• 2.5 V
• 0.4 V