MAH-MHT CET (PCM/PCB) entrance exam Question Bank Solutions

In a capillary tube of radius R, a straight thin metal wire of radius r (R > r) is inserted symmetrically and one end of the combination is dipped vertically in water such that the lower end of the combination is at same level. The rise of water in the capillary tube is ______.

[T = surface tension of water, ρ = density of water and g = gravitational acceleration]

If a capillary tube of radius 1 mm is immersed in water, the mass of water rising in the capillary tube is m. If the radius of the capillary tube is doubled, then the mass of water that rises in the same capillary tube will be ______.

A square surface of side l (m) in the plane of the paper. A uniform electric field E(V/m) also in the plane of the paper is limited only to the lower half of the square surface, the electric flux (in SI units) associated with the surface is ______.

What work must be done to rotate an electric dipole through an angle θ with the electric field, if an electric dipole of moment p is placed in a uniform electric field E with p parallel to E?

Eight dipoles of charges of magnitude e each are placed inside a cube. The total electric flux coming out of the cube will be ______. 

Water rises to a height of 3.2 cm in a glass capillary tube. Find the height to which the same water rises in another capillary having half the area of the cross-section.

Water rises to a height of 20 mm in a capillary. If the radius of the capillary is made one-third of its previous value, then the new value of capillary rise will be ______.

Water rises in a capillary tube through a height h. If the tube is inclined to the liquid surface at 45°, the liquid will rise in the tube upto its length equal to ______.

A large open tank containing water has two holes to its wall. A square hole of side 'a' is made at a depth 'y' and a circular hole of radius 'r' is made at a depth 16y from the surface of water. If equal amount of water comes out through both the holes per second, then the relation between r and a will be ______.

A string is stretched between fixed points separated by 75.0 cm. It is observed to have resonant frequency of 420 Hz and 315 Hz. There are no other resonant frequencies between these two. Then, the lowest resonant frequency for this string is ____________.

At temperature T, the emissive power and absorption power of a body for certain wavelength are `"e"_lambda` and `"a"_lambda` respectively, then ____________.

A thin circular ring of mass M and radius r is rotating about its axis with a constant angular velocity `omega`. Two objects of mass m are attached gently to the opposite ends of diameter of the ring. The wheel will now rotate with angular velocity ______.

Consider the circuit shown in the figure. The current I₃ is equal to ____________.

If the radius of earth contracts to half of its value today, (the mass remaining unchanged), then the duration of the day will be ____________.

A large vessel completely filled with water has two holes 'A' and 'B' at depths 'h' and '4h' from the top. Hole 'A' is a square of side 'L' and hole 'B' is circle of radius 'R'. If from both the holes same quantity of water is flowing per second, then side of square hole is ______.

In stream-line flow of liquid, the total energy of Liquid is constant at ____________.

Half part of an ice block is covered with black cloth and rest half is covered with white cloth and then it is kept in sunlight. After some time, clothes are removed to see the melted ice. Which of the following statements is correct?

Kirchhoff's law of radiation proves that a good emitter is a ______.

Select the CORRECT statement.

Two spherical black bodies of radius r₁ and r₂ with surface temperature T₁ and T₂ respectively, radiate same power, then r₁ : r₂ is ______.