Chapter 15 Test

Electric Work - is the work done by ____________k

• Electricity

• Ampere

• Current

• Voltage

Magnitude of Electrical work (W) depends on....

• Applied Voltage

• Current passed through the object

• Time

• All of it

Equation for work is.....

• W = U x I x b

• W = U x I x c

• W = U x I x cc

• W = U x I x t

Unit for mechanical power is ....

• W (watt)

• P (power)

• F (force)

• A (ampere)

Electric power =

• (Electric work)/SPACE

• (Electric work)/hours

• (Electric work)/minutes

• (Electric work)/time

If an appliance has a current of 10A and a voltage of 3V, what is the power?

• 10A - 3V = 7W

• 10A + 3V = 13W

• 10A x 3V = 30W

• 10A x 3V = 300W

If you have an electrical appliance, the resistance is 3Ω，applied voltage is 9V, what is the power?

• I = V/R → 9V/3Ω = 3A

  3A x 9V = 27W

• I = V/R → 9V/3Ω = 4A

  4A x 9V = 36W

• I = V/R → 9A/3V = 3A

  3A x 9V = 27W

• I = V/R → 9V/3Ω = 3A

  3A x 9V = 29W

Consume

Electrical appliances

Actual power

Rated current

means...

• 消耗

  用电器

  实际

  功

  额定

  电

• 消耗

  用电器

  实际

  功率

  额定

  电流

• 消

  用电

  实际

  功率

  额定

  电流

• 耗

  电器

  实际

  功率

  定

  电流

If you have an electrical appliance, the resistance is 5Ω，applied voltage is 15V, what is the power?

• Current = 15V / 5Ω = 3A

     P = VI = 15V × 3A = 54W

• Current = 15V / 5Ω = 3A

     P = VI = 15V × 3A = 40W

• Current = 15V / 5Ω = 3A

     P = VI = 15V × 3A = 55w

• Current = 15V / 5Ω = 3A

     P = VI = 15V × 3A = 45W

 1 kiloWatt =

• 1000A

• 1000W

• 1000

• 10W