NEET 2017 APRA
For the following questions answer them individually
The bulk modulus of a spherical object is ‘B’. If it is subjected to uniform pressure ‘p’, the fractional decrease in radius is
The acceleration due to gravity at a height 1 km above the earth is the same as at a depth d below the surface of earth. Then
The diagrams below show regions of equipotentials.
A positive charge is moved from A to B in each diagram.
Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time $$t_1.$$ On other days, if she remains stationary on the moving escalator, then the escalator takes her up in time $$t_2.$$ The time taken by her to walk up on the moving escalator will be
Two blocks A and B of masses 3m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively
A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be
Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are $$K_1 and K_2.$$ The thermal conductivity of the composite rod will be
One end of string of length l is connected to a particle of mass ‘m’ and the other end is connected to a small peg on a smooth horizontal table. If the particle moves in circle with speed ‘v’, the net force on the particle (directed towards center) will be (T represents the tension in the string)
In a common emitter transistor amplifier the audio signal voltage across the collector is 3 V. The resistance of collector is $$3 kΩ$$. If current gain is 100 and the base resistance is $$2 kΩ$$, the voltage and power gain of the amplifier is
Which of the following statements are correct?
(a) Centre of mass of a body always coincides with the centre of gravity of the body.
(b) Centre of mass of a body is the point at which the total gravitational torque on the body is zero
(c) A couple on a body produce both translational and rotational motion in a body.
(d) Mechanical advantage greater than one means that small effort can be used to lift a large load.
