Physics

For real object match the corresponding entries of column-1 with column-2 (where m is the magnification produced by the mirror) :-

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 :