Question

Filament lamp designed to work at a potential difference 250v has power 100w. what will be the power of this lamp when connected to a 100v supply?

Answer 1

Answer:

16,14,10,100,1,2,3,4z5,6,7,8,9,

Answer 2

Answer:

The power of the filament lamp when connected to a 100 volt supply, is 16 watts.

Explanation:

• The total amount of electrical energy required to transfer in a particular unit of time is called electric power.
• The S.I unit used for power is the watt.
• Power is often expressed in two different formulas;

                            Power (P) = Voltage(V)²÷ Resistance(R)

   or,

                           Power (P) = Current (I)² × Resistance(R)

Step-1

The given filament lamp has,

                                     V = 250 volt

                                     P = 100 watt

   we know that,         P = V² ÷ R

                          ∴        R = V² ÷ P

                                    R = (250)² ÷ 100

                                       = 625 Ω

Step-2

Now, we have the resistance of the filament lamp and new voltage supply is given as,

                                  V (new) = 100 volt

                                  R = 625 Ω

And we know,          P = V² ÷ R

                    ∴          P = 100² ÷ 625 = 16 watt

Thus the power of the filament lamp is 16 watt.