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Assertion (A) - When constant current is passing through a conductor of variable area of cross section, electric field inside conductor is inversely proportional to cross sectional area.

 

The current gain for a common emitter transister is 69. If the emitter current is 7 mA then base current will be

A radioactive sample decays by 63% of its initial value in 10s. It would have decayed by 50% of its initial value in :-

An object 1 cm tall is placed at 4 cm infront of a mirror, In order to produce an upright image of 3 cm height one needs a :-

In a step up transformer, if ratio of turns of primary to secondary is 1 : 10 and primary voltage is 230 V. If the load current is 2A, then the current in primary is :-

In the above diagram, balance length for E' is ℓ₀. If cross sectional area of wire AB is doubled then what will be new balancing length ?

Two pipes are each 50 cm in length. One of them is closed at one end while the other is open at both ends. The speed of sound in air is 340 m s^–1. The frequency at which both the pipes can resonate is :-

A particle is executing S.H.M. its potential energy v/s displacement graph is given by

The value of restoring force constant is :-

The molecules of a given mass of a gas have r.m.s. velocity of 200 m/s at 127°C and 1.0 × 105 N/m2 pressure. When the temperature and pressure of the gas are respectively, 227°C and 0.05 × 10⁵ N/m², the r.m.s. velocity of its molecules is :

Which of the following material is most suitable for making cooking utensil?

Length v/s temperature graph of A and B is given below. Find the relation between αA & αB.

A capillary glass tube records a rise of 20 cm when dipped in water. When the area of cross- section of the tube is reduced to half of the former value, water will rise to a height of:-

Kindly go through the solution 

Energy required to shift a body of mass m from an orbit of radius 2R to 3R is (mass of planet is M)

When a disc is rolling on level surface the percentage of its total kinetic energy which is translational, is nearly

A flywheel of moment of inertia 3 × 10^–2 kg m² is rotating with angular velocity of 10 rad/sec. The torque (constant) required to bring it rest in 2 sec will be