Physics Test - ...

The ratio of wavelengths of proton and deuteron accelerated through the same potential difference will be

Two radio antennas radiating waves in phase are located at point A and B, 200 m part (Figure). The radio waves have a frequency of 6 MHz. A radio receiver is moved out from point B along a line perpendicular to the line connecting A and B ( line BC shown in figure). At what distances from B will there be destructive interference ?

A bob is hanging over a pulley inside a car through a string. The second end of the string is in the hand of a person standing in the car. The car is moving with constant acceleration 'a' directed horizontally as shown in figure. Other end of the string is pulled with constant acceleration 'a' vertically.The tension in the string is equal to :

A transistor-oscillator using a resonant circuit with an inductor L (of negligible resistance) and a capacitor C in series produce oscillations of frequency . If L is doubled and C is changed to 4C, the frequency will be

The combination of 'NAND' gates shown here (in figure), are equivalent to

Two long coaxial and conducting cylinders of radius a and b are separated by a material of conductivity  $\sigma$ and a constant potential difference V is maintained between them, by a battery. Then the current, per unit length of the cylinder flowing from one cylinder to the other is :

A uniform sphere has a mass M and radius R. Find the pressure p inside the sphere, caused by gravitational compression, as a function of the distance r from its centre.  ($\gamma$ is universal gravitational constant )

A solid conducting sphere having a charge Q is surrounded by an uncharged concentric conducting hollow spherical shell. Let the potential difference between the surface of the solid sphere and that of the outer surface of the hollow shell be V. If the shell is now given a charge of –3Q, the new potential difference between the same two surfaces is

A wooden cylinder of mass 20 g and area of cross-section 1 cm², having a piece of lead of mass 60 g attached to its bottom floats in water. The cylinder is depressed and then released.

Estimate the maximum magnitudes of the electric and magnetic fields of the light that is incident on this page because of the visible light coming from your desk lamp. Treat the bulb as a point source of electromagnetic radiation, i.e., about 5% efficient in converting electrical energy to visible light.
(HINT: assume 60W bulb and a distance of 0.3 m)