If the current through a bulb changes by 1%,w | vedclass

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

Question

(B) The power consumed by a bulb is given by the formula $P = i^2R$,where $i$ is the current and $R$ is the resistance.Since $R$ is constant,we have $

Vedclass · Accepted Answer

$2$

Vedclass · Answer

(B) The power consumed by a bulb is given by the formula $P = i^2R$,where $i$ is the current and $R$ is the resistance.Since $R$ is constant,we have $P \propto i^2$.Taking the derivative or using the approximation for small changes,we get $\frac{\Delta P}{P} = 2 \frac{\Delta i}{i}$.Given that the percentage change in current is $\frac{\Delta i}{i} 	imes 100 = 1\%$.Therefore,the percentage change in power is $\frac{\Delta P}{P} 	imes 100 = 2 	imes (\frac{\Delta i}{i} 	imes 100) = 2 	imes 1\% = 2\%$.Thus,the power consumed changes by $2\%$.

If the current through a bulb changes by $1\%$,what is the percentage change in the power consumed?

Similar Questions

You are given three bulbs of $25\, W$,$40\, W$,and $60\, W$. Which of them has the lowest resistance?

In an electric heater, $4\, A$ current passes for $1\, \text{minute}$ at a potential difference of $250\, V$. The power of the heater and the energy consumed will be, respectively:

An expression for the rate of heat generated,if a current of $I$ ampere flows through a resistance of $R$ $\Omega$,is

Which of the following is not a unit of power?

$A$ lamp of $60 \, W, 230 \, V$ is used for $8 \, \text{hours}$. If the cost of $1 \, \text{unit}$ is $1.25 \, \text{Rs}$, what will be the total bill in $Rs$?

Vedclass Test Series

Exam Paper Generator

Online Exam Module