List of top Questions asked in MET- 2011

Rn decays into Po by emitting an \( \alpha \)-particle with half-life of 4 days. A sample contains \( 6.4 \times 10^{10} \) atoms of Rn after 12 days, the number of atoms of Rn left in the sample will be:

The energy gap between the valence and conduction bands of an insulator is about:

In Millikan’s oil drop experiment, a charged drop of mass \( 1.8 \times 10^{-13} \, \text{kg} \) is stationary between its plates. The distance between its plates is 0.9 cm, and the potential difference is 2000 V. The number of electrons in the drop is:

Decay constant of radium is \( \lambda \). By a suitable process its compound radium bromide is obtained. The decay constant of radium bromide will be:

A fighter plane is moving in a vertical circle of radius \( r \). Its minimum velocity at the highest point \( A \) of the circle will be:

A particle moves in the \( xy \)-plane under the action of a force \( F \) such that the components of its linear momentum \( p \) at any time \( t \) are \( p_x = 2 \cos t \), \( p_y = \sin t \). The angle between \( F \) and \( p \) at time \( t \) is:

A thin prism \( P_1 \) of angle 4° and refractive index 1.54° is combined with another thin prism \( P_2 \) of refractive index 1.72 to produce dispersion without deviation. The angle of \( P_2 \) is

While viewing a distant object with a telescope suddenly a housefly sits on objective lens. The correct statement is that

Two slits 4 mm apart, are illuminated by light of wavelength 6000 A. What will be the fringe width on a screen placed 2 m from the slits?

A charge of \( 10^{-9} \, \text{C} \) is placed on each of the 64 identical drops of radius 2 cm. They are then combined to form a bigger drop. Its potential will be:

Two parallel conductors A and B of equal length carry currents i and 10 i, respectively, in the same direction. Then

An open pipe is suddenly closed at one end with the result that the frequency of the third harmonic of the closed pipe is termed to be higher by 100 Hz than the fundamental frequency of the open pipe. The fundamental frequency of the open pipe is

As the temperature of hot junction increases, the thermo emf

A proton and an \( \alpha \)-particle enter a uniform magnetic field perpendicularly with the same speed. If proton takes 25 \( \mu \)s to make 5 revolutions, then the periodic time for the \( \alpha \)-particle would be

Which of the following statements is wrong?

Chance favours the trained mind. This statement was made by