A battery of emf $$10\,V$$ and internal resistance $$0.5\,\Omega $$ is connected across a variable resistance $$R.$$ The value of $$R$$ for which the power delivered in it is maximum, is given by
A.
$$0.5\,\Omega $$
B.
$$1.0\,\Omega $$
C.
$$2.0\,\Omega $$
D.
$$0.25\,\Omega $$
Answer :
$$0.5\,\Omega $$
Solution :
According to maximum power transfer theorem, the power output across load due to a cell or battery is maximum, if the load resistance is equal to the internal resistance of cell or battery. Hence, value of $$R$$ will be $$0.5\,\Omega .$$
Releted MCQ Question on Electrostatics and Magnetism >> Electric Current
Releted Question 1
The temperature coefficient of resistance of a wire is 0.00125 per $$^ \circ C$$ At $$300\,K,$$ its resistance is $$1\,ohm.$$ This resistance of the wire will be $$2\,ohm$$ at.
The electrostatic field due to a point charge depends on the distance $$r$$ as $$\frac{1}{{{r^2}}}.$$ Indicate which of the following quantities shows same dependence on $$r.$$
A.
Intensity of light from a point source.
B.
Electrostatic potential due to a point charge.
C.
Electrostatic potential at a distance r from the centre of a charged metallic sphere. Given $$r$$ < radius of the sphere.