1. A torch bulb is rated 3V and 600mA. Calculate its resistance if it is lighted for 4 h.

Open in App

Solution

Here,
V = 3 Volt
I = 600 mA = 600/1000
= 0.6 A
Resistance is not dependent on time t, so 4 h time has no use.
We know by Ohm’s law
V = IR
=> R = V/I
=> R = 3/0.6 = 5Ω
Resistance of the bulb filament is 5 ohm

Suggest Corrections

Similar questions

Q. A torch bulb is rated 5v and 500mA calculate it's 1.power 2.Resistance 3.Energy consumed when it is lighted for 6 hours everyday.

A torch bulb is rated 2.5 V and 750 mA. Calculate (i) its power (in W), (ii) its resistance (in $Ω$ ) and (iii) the energy consumed (in J) if this bulb is lighted for four hours.

A torch bulb is rated 2.5 volts and 750 mA. Calculate:(i)it's resistance (ii) it's power (iii) energy consumed if this bulb is lighted for four hours.

A bulb is rated 5 V and 500 mA. Calculate its (a) power, (b) resistance, and (c) energy consumed when it is lighted for 4 hours.

A light bulb is rated at 125 W for a 250 V a.c., supply.
Calculate the resistance of the bulb.

Join BYJU'S Learning Program

1. A torch bulb is rated 3V and 600mA. Calculate its resistance if it is lighted for 4 h.

Here,V = 3 VoltI = 600 mA = 600/1000 = 0.6 AResistance is not dependent on time t, so 4 h time has no use.We know by Ohm’s lawV = IR=> R = V/I=> R = 3/0.6 = 5ΩResistance of the bulb filament is 5 ohm

Here,
V = 3 Volt
I = 600 mA = 600/1000
= 0.6 A
Resistance is not dependent on time t, so 4 h time has no use.
We know by Ohm’s law
V = IR
=> R = V/I
=> R = 3/0.6 = 5Ω
Resistance of the bulb filament is 5 ohm