Question

Draw a circuit diagram of an electric circuit containing a cell,akey,an ammeter a resistor of $4$ in series with a combination of two resistors each in parallel and a voltmeter across parallel combination.Each of them dissipate maximum energy and can withstand a maximum power of $16$ w without melting. Find the maximum current that can flow through the three resistors.

Answer 1

Here the circuit in which a resistor of resistance 4Ω is attached in series and two resistors of resistance 8Ω are attached in parallel. Also, Ammeter and voltmeter attached in the circuit in series and parallel respectively.

Now,

Maximum power of each resistor is 16W

4Ω resistor is joined in series with circuit .

so, $Power=i^{2}R$ , here i is current through resistor of resistance R

$16=i^2\ast 4\Omega$

i = 2A

Now, 2A is passing through parallel resistors of resistance 8Ω.

we know, in parallel potential difference be constant so,

current divides two part , due to same resistance current on each resistance will be half . so, current passing through each parallel resistor is $\frac{2}{2A}=1A$

So, finally current through 4Ω resistor $=2A$

current through each 8Ω resistor $=1A$