Unit 4 - Electricity

1
Electricity Formulas

I V V R
I R P VI
E P t Voltage in Volts(V), Current in Amps
(A), Resistance in Ohms (O), Power in Watts
(W) or Kilowatts(kW) Energy in Kilowatt-Hours(kWh)
, time in hours (h)
2

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 25kWh P E/t E t
• t 3h
• V 110V
• I ?

3

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h
• V 110V
• I ?

4

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h P 5kW
• V 110V
• I ?

5
Electricity Formulas

I V V R
I R P VI
E P t Voltage in Volts(V), Current in Amps
(A), Resistance in Ohms (O), Power in Watts
(W) or Kilowatts(kW) Energy in Kilowatt-Hours(kWh)
, time in hours (h)
6

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h P 5kW 5000W
• V 110V
• I ?

7

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h P 5kW 5000W
• V 110V
• I ? I P/V

7
8

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h P 5kW
• V 110V
• I ? I P/V 5000W 110V
  

9

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h P 5kW 5000W
• V 110V
• I ? I P/V 5000W 110V
  
• I 45.5

10
Electricity Formulas

I V V R
I R P VI
E P t Voltage in Volts(V), Current in Amps
(A), Resistance in Ohms (O), Power in Watts
(W) or Kilowatts(kW) Energy in Kilowatt-Hours(kWh)
, time in hours (h)
11

• 3) In a stereo, the energy being used is 15kWh.
  If it is used for 3h and the voltage of the
  stereo is 110V, find the current.
• E 15kWh P E/t E t 15 kWh
  3 h
• t 3h P 5000W
• V 110V
• I ? I P/V 5000W 110V
  
• I 45.5 A
• The current is 45.5 A.

12
7.
13
V 30V V 9V
P 192 000 W R 0. 323 O P 111.1W
I 2.29A

P 24 576W

61
7.
14
Ohms Law Electricity Problems
Voltage Current Resistance Power time Energy
1 12V 2A 2000h
2 5.5A 20O 3000h
3 8V 1.5A 9000h
4 100V 0.5 A 2500h
5 24V 0.25A 200h
6 2A 60O 50h
7 50V 0.5A 150h
8 75V 0.3A 900h
9 120V 30O 500h
10 120V 500mA 2h
11 220V 0.75A 5h
12 2000mA 4.5O 20h