JEE Main Test 9...

When the current changes from + 2 A to -2 A in 0.05 s, an emf of 8V is induced in a coil. The coefficient of self induction of the coil is

The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is B₀ = 510 nT. What is the amplitude of the electric field part of the wave?

To an evacuated vessel with movable piston under external pressure of 1 atm, 0.1 mole of He and 1.0 mole of an unknown compound (vapour pressure 0.68 atm at 0°C) are introduced. Considering the ideal gas behaviour, the total volume (in litre) of the gases at 0°C is close to

The dielectric constant of air is 1.006. The speed of electromagnetic wave travelling in air is a × 10⁸ ms^-1, where, a is about

Dalton's law of partial pressure is not applicable to

If θ is the angle between the tangents from (-1, 0) to the circle x² + y² - 5x + 4y = 0, then θ is equal to

If the line y - √3x + 3 = 0 cuts the parabola y² = x + 2 at A and B, then PA. PB is equal to [where, P = (√3, 0)]

Two light rays having the same wavelength λ in vacuum are in phase initially. Then, the first ray travels a path L₁ through a medium of refractive index n₁ while the second ray travels a path of length L₂ through a medium of refractive index n₂. The two waves are then combined to produce interference. The phase difference between the two waves is

The decreasing order of bond dissociation energies of C—C, C—H and H—H bonds is

In which of the following reactions, the heat liberated is known as "heat of combustion" ?