List of practice Questions

A thermodynamic system is taken through the cycle abcda. The work done by the gas along the path bc is :

Consider the following statements A and B and identify the correct answer:

A. For a solar-cell, the I-V characteristics lies in the IV quadrant of the given graph.
B. In a reverse biased pn junction diode, the current measured in (µA), is due to majority charge carriers.

A bob is whirled in a horizontal plane by means of a string with an initial speed of ω rpm. The tension in the string is T. If speed becomes 2ω while keeping the same radius, the tension in the string becomes:

Given below are two statements:
Statement I: Atoms are electrically neutral as they contain equal number of positive and negative charges.
Statement II: Atoms of each element are stable and emit their characteristic spectrum.
In the light of the above statements, choose the most appropriate answer from the options given below

The graph which shows the variation of \(\big(\frac{1}{\lambda^2} \big)\)and its kinetic energy, is \(E\) (where \(λ\) is de Broglie wavelength of a free particle):

In an ideal transformer, the turns ratio is \(N_p/N_s\) =1/2 .The ratio \(V_S:V_P\) is equal to (the symbols carry their usual meaning):

A tightly wound \(100\) turns coil of radius \(10 cm\) carries a current of \( 7 A\). The magnitude of the magnetic field at the centre of the coil is (Take permeability of free space as \(4\pi×10^{-7}\) SI units):

A horizontal force 10 N is applied to a block 4 as shown in figure. The mass of blocks A and B are 2 kg and 3 kg, respectively. The blocks slide over a frictionless surface. The force exerted by block A on block B is:

A wire of length and resistance \(100\) is divided into 10 equal parts. The first \(5\) parts are connected in series while the next \(5\) parts are connected in parallel. The two combinations are again connected in series. The resistance of this final combination is:

In a uniform magnetic field of \(0.049 T\), a magnetic needle performs \(20\) complete oscillations in \(5\) seconds as shown. The moment of inertia of the needle is \(9.8 \times 10 kg m^2\). If the magnitude of magnetic moment of the needle is \(x \times 10^{-5} Am^2\); then the value of '\(x\)' is

The terminal voltage of the battery, whose emf is\(10V\) and internal resistance\(1Ω\), when connected through an external resistance of \(4Ω\) as shown in the figure is:

A logic circuit provides the output y as per the following truth table:

A	B	Y
0	0	1
0	1	0
1	0	1
1	1	0

The expression for the output Y is:

If the monochromatic source in Young's double slit experiment is replaced by white light,
1. There will be a central dark fringe surrounded by a few coloured fringes
2. There will be a central bright white fringe surrounded by a few coloured fringes
3. All bright fringes will be of equal width
4. Interference pattern will disappear

In a Vernier caliper, \(N+1\) divisions of vernier scale coincide with \(N\) divisions of main scale. If 1 MSD represents 0.1 mm, the vernier constant (in cm) is: