Question

A torch bulb is rated 2.5V and750miliampere. Calculate it's power,it's resistance, energy consumed by bulb light for 4 hours

Answer 1

hello...


V = 2.5 V

I = 750 mA = 0.75 A

t = 4 hours = 4*3600 s = 14400 s



(a) P = VI

= 2.5*0.75

= 1.875 W



(b) R = V/I

= 2.5/0.75

= 3.33 Ω



(c) H = Pt

= 1.875x14400

= 27000 J or 27 kJ


thank you...

☺

Answer 2

a. v = 2.5v

b. i = 750ma = 0.75a

power = current × voltage

0.75 × 2.5

power = 1.875watt

b. we know that

r = v2/p

2.5 ×2.5/1.875

6.25/1.875

r= 3.33ohm

c. energy= power×time

1.875 × 14400

e= 27000J or 27KJ