Question

2. Answer following question related to the circuit shown below. The light bulbs used in this circuits (a,b,c) have the same rating: 2.51 -0.74W. 2.8V O (1) Estimate the resistance of the light bulb using the rating information. (2) Estimate the total resistance of the circuit. (You can solve this by estimating the overall resistance of light bulb (b) & (c) first, and then add the resistance of light bulb (a).) (3) Estimate the net current of the circuit. (Use your answer from (2)) (4) Estimate the power consumption of each light bulb. (5) Rank the brightness of the lightbulb. (brightest to dimmest) (6) What kind of brightness change you expect to see from the light bulb (b) and (c) if you take off light bulb (a) from the socket? (7)After putting the light bulb (a) back, you take the light bulb (b) off from the socket. What kind of brightness change you expect to see from the light bulb (a) and (c)? (8) After putting the light bulb (b) back, you take the light bulb (c) off from the socket. What kind of brightness change you expect to see from the light bulb (a) and (b)?

Answer 1

Rbulb = 8.4462, Q. (5) More power, more bright P = I2R P & I2 [as R = sam 25 - 10 or brightness A>B=0 Req r Reg so, I azu Ia> I a So, I'm II > I = I c u more bright now as > Reg, so I a < Ia Rega Rut R2 = 36 Now Res= 2R ya 3R a = Z, I a= 24 and I = Ic - Ig = 7 - BR . Ia's Ia so brightness of a decreases (as R 1.5=sane I = I al > I brightness of b increases each bulb bec symmetrical. I bulb] So, from brightness 9 (2 of a decreases [ symmetry with b Encreases questio [symmetry with Vh