An electric bulb rated for $500\, watts$ at $100\, volts$ is used in a circuit having a $200-volt$ supply. The resistance $R$ that must be put in series with the bulb, so that the bulb draws $500\, W$ is .................. $\Omega$
Medium
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1A copper rod of cross-sectional area $A$ carries a uniform current $I$ through it. At temperature $T$, if the volume charge density of the rod is $\rho $, how long will the charges take to travel a distance $d$ ?View Solution
- 2The resistance of a wire is $R$. If the length of the wire is doubled by stretching, then the new resistance will beView Solution
- 3A railway compartment is lit up by thirteen lamps each taking $2.1\, amp$ at $15\, volts$. The heat generated per second in each lamp will be ............ $cal$View Solution
- 4The resistance of the filament of an electric bulb changes with temperature. If an electric bulb rated $220\, volt$ and $100\, watt$ is connected $(220 \times 0.8)$ $volt$ sources, then the actual power would beView Solution
- 5In the following $'I'$ refers to current and other symbols have their usual meaning, Choose the option that corresponds to the dimensions of electrical conductivityView Solution
- 6A current of $2\, mA$ was passed through an unknown resistor which dissipated a power of $4.4\, W$. Dissipated power when an ideal power supply of $11\, V$ is connected across it isView Solution
- 7View SolutionConstantan wire is used in making standard resistances because its
- 8In potentiometer experiment when $K_1$ is closed balance length is $100\,cm$. Then what will be balancing length when $K_2$ is closed ................ $\mathrm{cm}$View Solution
- 9$100$ cells each of $e.m.f.$ $5\, V$ and internal resistance $1\, ohm$ are to be arranged so as to produce maximum current in a $25\, ohms$ resistance. Each row is to contain equal number of cells. The number of rows should beView Solution
- 10Four ammeters with identical internal resistance $r$ and a resistor $R$ are connected to a current source as given. if reading of $A_1$ and $A_2$ is $3\ A$ and $5\ A$ respectively then the reading $A_4$ is ............. $A$View Solution
