Two electric bulbs marked 25 W - 220 V and 10 | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) First,calculate the resistance of each bulb using $R = V^2 / P$:$R_1 = (220)^2 / 25 = 1936\ \Omega$$R_2 = (220)^2 / 100 = 484\ \Omega$The total re

Vedclass · Accepted Answer

$25\ W$

Vedclass · Answer

(D) First,calculate the resistance of each bulb using $R = V^2 / P$:$R_1 = (220)^2 / 25 = 1936\ \Omega$$R_2 = (220)^2 / 100 = 484\ \Omega$The total resistance in series is $R_{eff} = R_1 + R_2 = 1936 + 484 = 2420\ \Omega$.The current flowing through the series circuit is $I = V_{supply} / R_{eff} = 440 / 2420 = 44 / 242 = 2 / 11\ A \approx 0.1818\ A$.Now,calculate the maximum rated current for each bulb using $I_{rated} = P / V$:For the $25\ W$ bulb: $I_{1,rated} = 25 / 220 = 5 / 44 \approx 0.1136\ A$.For the $100\ W$ bulb: $I_{2,rated} = 100 / 220 = 5 / 11 \approx 0.4545\ A$.Comparing the circuit current $I$ with the rated currents:Since $I (0.1818\ A) > I_{1,rated} (0.1136\ A)$,the $25\ W$ bulb will fuse.Since $I (0.1818\ A) < I_{2,rated} (0.4545\ A)$,the $100\ W$ bulb will not fuse.

Two electric bulbs marked $25\ W - 220\ V$ and $100\ W - 220\ V$ are connected in series to a $440\ V$ supply. Which of the bulbs will fuse?

Similar Questions

As the temperature of the hot junction of a thermocouple is increased (while the cold junction is at a constant temperature), the thermo $e.m.f.$

$A$ cable consists of a copper wire of radius $9 \, mm$ having a resistance of $5 \, \Omega$. If this cable is replaced by $6$ copper wires each of radius $3 \, mm$,what will be the new resistance of the cable in $\Omega$?

Two voltmeters $V_1$ and $V_2$ are connected in series in a $D.C.$ circuit. The reading of $V_1$ is $80 \, V$ and its sensitivity is $200 \, \Omega/V$. If the resistance of $V_2$ is $32 \, k\Omega$,what is the total voltage of the circuit in $V$?

Two rods of copper $(Cu)$ and iron $(Fe)$ with the same cross-sectional area are joined at $S$ and a steady current $I$ flows through the rods as shown in the figure. Choose the most appropriate representation of charges accumulated near the junction $S$.

The thermo emf of a hypothetical thermocouple varies with the temperature $\theta$ of the hot junction as $E = a\theta + b\theta^2$ in volts,where the ratio $a/b$ is $700^{\circ}C$. If the cold junction is kept at $0^{\circ}C$,then the neutral temperature is:

Vedclass Test Series

Exam Paper Generator

Online Exam Module