Question

٠Light bulb A is rated at 60 W and light bulb B is rated at 100 W. Both are designed to operate at 110 V. Which statement is correct?
A-The 60 W bulb has a greater resistance and greater current than the 100 W bulb.

B-The 60 W bulb has a greater resistance and smaller current than the 100 W bulb.

C-We need to know the resistivities of the filaments to answer this question.

D-The 60 W bulb has a smaller resistance and greater current than the 100 W bulb.

F-The 60 W bulb has a smaller resistance and smaller current than the 100 W bulb

Answer 1

Answer:B

Explanation:

Power=p

Voltage=v

Resistance=r

Voltage for both:110v

For 60 watts bulb:

Resistance=v^2/p

Resistance=110^2/60

Resistance=(110x110)/60

Resistance=12100/60

Resistance=201.7 ohms

Current=power/voltage

Current=60/110

Current=0.55 amperes

For 100watts bulb:

Resistance=v^2/p

Resistance=110^2/100

Resistance=(110 x 110)/100

Resistance=(12100)/100

Resistance =121 ohms

Current=power/voltage

Current=100/110

Current=0.91