NEET (UG) entrance exam Question Bank Solutions

If numerical aperture of a microscope is increased then it

The phenomenon of photoelectric emission was observed by ______.

Three identical spheres, each of mass M, are placed at the comers of a right angle triangle with mutually perpendicular sides equal to 2 m (see figure). Taking the point of intersection of the two mutually perpendicular sides as the origin, find the position vector of centre of mass.

A flywheel at rest is to reach an angular velocity of 24 rad/s in 8 second with constant angular acceleration. The total angle turned through during this interval is ______.

A transverse harmonic wave of amplitude 0.01 m is generated at one end of a long horizontal string by a tuning fork of frequency 500 Hz. At a given instant of time, the displacement of a particle at a distance of 0.2 m from the fork is – 0.005 m and that of a particle at a distance of 0.1 m is + 0.005 m. The wavelength is

An iceberg of density 700 kg/m³ is floating in the water of density 1000 kg/m³. The percentage of the volume of ice cube outside the water is:

The surface tension of a liquid is 10 N/m. If a thin film of the area 0.05 m² is formed on a loop. Then the surface energy will be:

In a capacitor of capacitance 20 µF the distance between the plates is 5 mm. If a dielectric slab of width 2 mm and dielectric constant 3 is inserted between the plates, then the new capacitor will be ______.

A body moving along a circular path of radius R with velocity v, has centripetal acceleration a. If its velocity is made equal to 2v. What will be the centripetal acceleration?

The capacity of the parallel plate condenser depends on ______

Two objects of masses 300 g and 700 g possess velocities `15 hat"i"` m/s and `4 hat"i" + 6 hat"j"` m/s respectively. The velocity of their centre of mass in m/s is:

A mass M suspended from a light spring which is fixed at the upper end to rigid support oscillates in a vertical line with a period of 2 s. If the mass is increased by 20 g, then the time period of oscillation increases by 1 s. The value of M is ______. 

The dimensions of magnetic induction are ______

In Geiger - Marsden scattering experiment, the trajectory traced by an α-particle depends on ______.

When an α-particle happens to come near a nucleus the intense electric field of these scatters it through a large angle then what is the effect of atomic electrons on α-particle?

The S.I. unit of pole strength is ______

An intrinsic semiconductor has a resistivity of 0.50 Ω m at room temperature. Find the intrinsic carrier concentration if the mobilities of electrons and holes are 0.39 m²V^-1S^-1 and O.11 m² v^-1S^-1 respectively:

If a body is moving in a circle of radius r with a constant speed v, its angular velocity is ______.

If the net external force acting on the system of particles is zero, then which of the following may vary?

The equation of a simple harmonic progressive wave is given by y = A sin (100πt − 3x). Find the distance between 2 particles having a phase difference of `π/3`.