The resistance of a bulb filament is $100\, \Omega$ at a temperature of $100^?C$ . If its temperature coefficient of resistance be $0.005$ per $^?C$ , its resistance will become $200\,\Omega$ at a temperature of:

Let resistance of bulb filament is $R_0$ at $0^?C$ then from expression $R_{\theta}=R_{0}\left[1+\alpha\Delta\theta\right]$ we have, $100=R_{0}\left[1+0.005\times100\right]$ and $200=R_{0}\left[1+0.005\times x\right]$ where $x$ is temperature in $^?C$ at which resistance become $200\,\Omega$ . Dividing the above two equations $\frac{200}{100}=\frac{1+0.005x}{1+0.005\times100} \Rightarrow x=400^?C$

The resistance of a bulb filament is $100\, \Omega

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Current Electricity

Current electricity is defined as the flow of electrons from one section of the circuit to another.

Types of Current Electricity

There are two types of current electricity as follows:

Direct Current

The current electricity whose direction remains the same is known as direct current. Direct current is defined by the constant flow of electrons from a region of high electron density to a region of low electron density. DC is used in many household appliances and applications that involve a battery.

Alternating Current

The current electricity that is bidirectional and keeps changing the direction of the charge flow is known as alternating current. The bi-directionality is caused by a sinusoidally varying current and voltage that reverses directions, creating a periodic back-and-forth motion for the current. The electrical outlets at our homes and industries are supplied with alternating current.

The resistance of a bulb filament is $100\, \Omega$ at a temperature of $100^?C$. If its temperature coefficient of resistance be $0.005$ per $^?C$, its resistance will become $200\,\Omega$ at a temperature of:

The Correct Option is B

Solution and Explanation

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