Physics Test - ...

The Bohr model is applicable to:

What are the charge carriers in semiconductors?

A convex lens of refractive index 1.49 is immersed in a certain liquid. For the lens to act as a transparent plane sheet, what should be the refractive index of the liquid?

A circular coil of radius \(10 ~cm, 500\) turns and resistance \(2 \Omega\) is placed with its plane perpendicular to the horizontal component of the earth's magnetic field. It is rotated about its vertical diameter through \(180^{\circ}\) in \(0.25 ~s\). Estimate the magnitudes of the emf and current induced in the coil. Horizontal component of the earth's magnetic field at the place is \(3.0 \times 10^{-5} ~T\):

On giving 220 V to a resistor the power dissipated is 40 watt, then the value of resistance is:

Which of the following gates serve as building blocks in digital circuits?

When a \(DC\) voltage of \(200 V\) is applied to a coil of self-inductance \(\left(\frac{2 \sqrt{3}}{\pi}\right) H ,\) a current of \(1 A\) flows through it. But by replacing the \(DC\) source with an \(AC\) source of \(200 V\), the current in the coil is reduced to \(0.5 A\). The frequency of the \(AC\) supply is:

Consider an excited hydrogen atom in state n moving with a velocity v (v<< c). It emits a photon in the direction of its motion and changes its state to a lower state m. Apply momentum and energy conservation principle to calculate the frequency v of the emitted radiation. Compare this with the frequency v₀ emitted if the atom were at rest.

Which of the following statement(s) are correct for the Bohr model?

If two bulbs, one of 200 W and the other of 100 W are connected in series with a 100 V battery, then which bulb will have more brightness: