If the value of gravitational acceleration at a height h above the Earth’s surface is the same as that at a depth d below the Earth’s surface (with both h and d small compared to the Earth’s radius R), then
Oil raise up the wick in a lamp. The principle involves
The distance between centre of the earth and moon is 384000 km. If the mass of the earth is 6 ´ 1024 kg and G = 6.66 ´ 10-11 Nm2/kg2. The speed of the moon is nearly
Which of the following does not obey Ohm’s law
If a rock is brought from the surface of the moon to the earth, then
The escape velocity from earth is 11.2 km per sec. If a body is to be projected in a direction making an angle 45° to the vertical, then the escape velocity is
92U235 undergoes successive disintegrations with the end product of 82Pb203. The Number of a and b particles emitted are
What is the minimum thickness of a thin film required for constructive interference in the reflected light from it?
Given, the refractive index of the film = 1.5, wavelength of the light incident on the film = 600 nm.
in 1666, Newton concluded that the force which caused an apple to fall to the ground and the force that kept the moon in its orbit around the earth is the ?
A man inside an artificial satellite feels weightlessness because the force of attraction due to earth is
The equation for the mass of earth is?
When a temperature rises, the drift velocity of the free electrons decreases. Hence for given applied voltage?
Given below are two statements:
Assertion (A): Universe is expanding.
Reason (R): The result is based on red shift of spectra of galaxies.
If the doors of a refrigerator are left open for a few hours, the room temperature will
Rainbow is produced when sunlight fall on drops of rain. Which of the following physical phenomena are responsible for this?
(i) Diffusion
(ii) Refraction
(iii) Internal reflection
The earth’s gravitational pull is just balanced by the centripetal force resulting into?
A battery of e.m.f. E has an internal resistance 'r'. A variable resistance R is connected to the terminals of the battery. A current I is drawn from the battery. V is the terminal P.D. lf R alone is gradually reduced to zero, which of the following best describes I and V?
The angle of reflection is equal to the angle of incidence.
Cp and Cv are specific heats at constant pressure and constant volume respectively. It is observed that Cp – Cv = a for hydrogen gas Cp – Cv = b for nitrogen gas
The correct relation between a and b is :
A man, standing between two cliffs, claps his hands and starts hearing a series of echoes at intervals of one second. If the speed of sound in air is 340 ms-1, the distance between the cliffs is _______.
According to Coulomb’s law, the electrostatic force between two charges is
The absorption of ink by blotting paper involves
What is the correct sequence in which the lengths of the following units increase?
1. Angstrom
2. Micron
3. Nanometer
Select the correct answer using the codes given below:
The mean radius of the earth is R, its angular speed on its own axis is w and the acceleration due to gravity at earth’s surface is g. The cube of the radius of the orbit of a geo-stationary satellite will be
Two cells each of emf E and internal resistance r are connected parallel across a resistor R. The power dissipated in the resistor is maximum if
The earth is not a perfect sphere, but it bulges at the?
A liquid drop tends to assume a spherical shape because of
If the gravitational force between two objects were proportional to 1/R (and not as 1/R2) where R is separation between them, then a particle in circular orbit under such a force would have its orbital speed v proportional to
Stars appears to move from east to west because