Physics Test - ...

A transformer having efficiency of \(90 \%\) is working on \(200 \mathrm{~V}\) and \(3 \mathrm{~kW}\) power supply. If the current in the secondary coil is \(6 \mathrm{~A}\), the voltage across the secondary coil and the current in the primary coil respectively are:

In a series LCR circuit \(\mathrm{R}=200 \Omega\) and the voltage and the frequency of the main supply is \(220 \mathrm{~V}\) and \(50 \mathrm{~Hz}\) respectively. On taking out the capacitance from the circuit the current lags behind the voltage by \(30^{\circ}\). On taking out the inductor from the circuit the current leads the voltage by \(30^{\circ}\). The power dissipated in the LCR circuit is:

Dimensions of \(\frac{1}{\mu_{0} \varepsilon_{0}}\), where symbols have their usual meaning, are:

The iron blade has a ring in which the wooden handle is fixed. The ring is slightly smaller in size than a wooden handle. The ring is heated. When the ring cools, it ______________ and tightly fits on the handle.

Thermal expansion of solids are:

Two circular loops \(A\) and \(B\) of radii \(r_{A}\) and \(r_{B}\) respectively are made from a uniform wire. If the ratio of their moments of inertia about axes passing through their centres and perpendicular to their planes is \(\frac{{I}_{{B}}}{{I}_{{A}}}=8\), then \(\left(\frac{{r}_{{B}}}{{r}_{{A}}}\right)=?\)

If momentum (p), area (A) and time (T) are taken to be fundamental quantities, then energy has the dimensional formula:

Which of the following is the reason for signal distortion in a communication system?

The electromagnetic waves travel with a velocity:

The work-energy theorem equates the change in the kinetic energy of an object to: