Physics Test - ...

In an LCR series circuit, the potential difference between the terminals of the inductance is 60 V, that between the terminals of the capacitor is 30 V and that across the resistance is 40 V. Then, the supply voltage will be ?

An electron jumps from the fourth orbit to the second orbit of hydrogen atom. If Rydberg’s constant R is equal to 10⁷ m^–1, then the frequency of the emitted radiation in Hz will be ?

The door of a running refrigerator inside a closed room was left open. Which of the following observations will be seen?

If the wavelength of incident light changes from 400 nm to 300 nm, then the stopping potential of photoelectrons emitted from a surface becomes (approximately).

A fully charged capacitor has a capacitance C. It is discharged through a small coil of resistance wire embedded in a thermally insulated block of specific heat capacity s and mass m. If the temperature of the block is raised by ΔT, then the potential difference V across the capacitor will be.

The electric potential at a point on the axis of an electric dipole depends upon the distance r (>> a) of the point from centre of the dipole as :

Two spherical bodies of masses 'M' and '5M' and radii 'R' and '2R', respectively, are released in free space with initial separation between their centres equal to '12R'. If they attract each other due to gravitational force only, then what is the distance covered by the smaller body just before collision?

The coercivity of a small magnet where the ferromagnet gets demagnetised is 3 x 10³ Am^–1. The current required to be passed in a solenoid of length 10 cm and number of turns 100, so that the magnet gets demagnetised when inside the solenoid, is :

A particle moves in xy plane according to the law x = a sin ωt and y = a(1 - cos ωt), where a and w are constant. The particle traces.

A parachutist, after bailing out, falls 50 m without friction. When parachute opens, it retards at 2 ms^-2. He reaches the ground with a speed of 3 ms^-1. At what height did he bail out?