Physics Ncert Solutions Class 12th

A signal containing multiple frequencies is shown in figure A. It is passed through 2 different filters and then outputs are shown in figure B & C.

A uniformly charged solid sphere having charge –9 coulomb and radius 2R is placed inside uniformly charged non conducting spherical shell of radius R and charge Q as shown in the figure. Find the value of Q (in coulomb), such that net electric field at P is zero_____.

A source of sound S is moving with a velocity of 50 m/s towards a stationary observer. The observer measures the frequency of the source as 1000 Hz. What will be the apparent frequency (in Hz) of the source when it is moving away from the observer after crossing him? (Take speed of sound in air as 350 m/s)

An antenna is mounted on a 400m tall building. What will be the wavelength of signal that can be radiated effectively by the transmission tower upto a range of 44kg?

Choose the correct waveform that can represent the voltage across R of the following circuit, assuming the diode is ideal one:

In the given circuit find the current through the Zener diode in mA.

The truth table for the circuit given in the figure is :

Calculate the value of output voltage V₀ (in V) if the Si diode and  Ge diode conduct at 0.7V and 0.3V respectively as shown in figure.

Assuming the sun to be a spherical body (e = 1) of radius R at a temperature of T K, evaluate the total radiant power, incident on Earth having radius r₀, at a distance r from the Sun, where r₀ is the radius of the earth and $\sigma$  is Stefan's constant.

At t  < 0, the capacitor is charged and the switch is opened. At t = 0 the switch is closed. The shortest time T at which the charge on the capacitor will be zero is given by: