IIT JAM Physics MCQ Test 6 - Physics MCQ

An alternating potential (V) = V sin cot is applied across a circuit. As a result the current  flows in it. The power consumed in the circuit per cycle is:- 

An ideal inductor takes current of 10 A when connected to a 125 V. 50 Hz ac supply. A pure resistor across the same source takes 12.5 A. If the two are connected in series across a 100 √2 v, 40 Hz supply, the current through the circuit will be

For a varying current  the R.M.S. value of current will be:

A circular loop of radius a' is made of single form of thin conducting wire. The self inductance of this loop is L'. If the no. of turns in the loop is increased from 1 to 8. the self inductance would be:-

An LR circuit with a battery is connected at t = 0, which of the following quantities is/are not zero just after the connection?

Which one of the following Maxwell's equations implies the absence of magnetic monopoles?

In a homogeneous non conducting region where  the value of ε₁ will be

Positive and negative point charges of equal magnitude are kept at  and  respectively.
The work done by the electric field when another positive point charge in moved from (-a. 0. 0) to (0. a. 0) is

A certain charge Q is divided into two parts q and (Q - q). For the maximum coulomb force between them, the ratio (q/Q) is:

A charge situated at a certain distance from an electric dipole in the end on position experiences a force F. If the distance of the charge is doubled, the force acting on the charge will be:

A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin. B be the point on the x-axis at = +1 cm and c be point on the y - axis at y = +1 cm. Then the potentials at the points A. B and C satisfy:

A disk of radius a/4 having a uniformly distributed charge 6C is placed 8c is placed on the x- axis from x =a/4 to x = 5a/4. Two point charge - 7 c and 3c are placed at (a/4. 0) and (-3a/4,3a/4.0), respectively, consider a cubical surface formed by six surfaces x = x = ±a/2.y = ±a/2.z = ±a/2. The electric flux through this cubical surface is

An electromagnetic wave whose electric field is given below 

E_z= 0

Which one of the following statements are incorrect?

Two long parallel wires of zero resistance are connected to each other by a battery of 1.0 V. The separation between the wires is 0.5 m. A metal bar, which is perpendicular to the wire and of resistance 10 Ω moves on these wires when a magnetic field of 0.02 tesla is acting perpendicular to the plane containing the bar and the wires. If the mass of the bar is 0.002 kg.

A conducting loop rotates with constant angular velocity about its fixed diameter in a uniform magnetic field in a direction perpendicular to that of fixed diameter

Which of the following are correct if electrostatic potential field is given by 

Consider the circuit shown below. Calculate the effective resistance of the circuit and use this knowledge to find the current (in Ampere) in the 4Ω resistor.

A potential difference of V is applied at the ends of a copper wire of length l and diameter d. On doubling only d, drift velocity 

Calculate the equivalent resistance between points C & D in the combination of resistance shown in figure.

Assuming that all the energy from a 2000 watt lamp is radiated uniformly, calculate the average values of the intensities of electric fields (in v/m) of radiation at a distance of 2 m from the lamp.

Calculate the magnitude of poynting vector (in mega watt/m²) at the surface of the sun. Given that power radiated by sun is 4 * 10²⁶ watts and radius of sun is 7 x 10⁸m ).

A container of volume 1 m³ is divided into two equal parts by a partition. One part has an ideal gas at 300 K and the other part is vacuum. The whole system is thermally isolated from the surroundings. When the partition is removed, the gas expands to occupy the whole volume. Its temperature will now be ____ .

During an experiment, an ideal gas is found to obey an additional law p²V = constant. The gas is initially at a temperature T and volume V. When it expands to a volume 2V. the temperature becomes ____ .

One mole of a monoatomic ideal gas is mixed with one mole of a diatomic ideal gas. The molar specific heat of the mixture at constant volume is ____ .

Let four point charges  and  -q/2 be placed at the verticies of a square of side a. Let another point charge -q be placed at the centre of the square Let v(r)  be the electrostatic potential at a point P at a distance r » a from the centre of the square. Then   is_____.

A cubical box of side 1 m contains helium gas (atomic weight 4) at a pressure of 100 N/m². During an abservation time of 1 s, an atom travelling with the root mean square speed parallel to one of the edges of the cube, was found to make 500 his with a particular wall, without any collision other atoms. Take,  Evaluate the temperature of the gas.