Question

sebuah lampu listrik dengan spesifikasi 220 v dan 50 w dihubungkan seri dengan sebuah hambatan listrik 1.000 ohm lalu dipasang pada sumber tegangan 110 volt. ini berarti bahwa arus yang mengalir pada rangkaian itu adalah... mA

Answer 1

consider the electric lamp

V = Voltage rating of the lamp = 220 Volts

P = power rating of the lamp = 50 watt

R = resistance of the lamp

Power is given as

P = V²/R

R = V²/P

inserting the values

R = 220²/50

R = 968 ohm

r = resistance connected in series with the lamp = 1000 ohms

E = emf of the Voltage source = 110 Volts

Since lamp and electrical resistor are in series , their combined resistance can be given as

R' = R + r

R' = 968 + 1000

R' = 1968 ohm

i' = current flowing in the circuit

Using ohm's law , current flowing in the circuit is given as

i' = E/R'

i' = 110/1968

i' = 0.0558 A

i' = 55.8 mA