HSC Science (Electronics) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions for Physics

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Charge + q and - q are placed at points A and B respectively which are distance 2L apart. C is the midpoint of A and B. The work done in moving a charge + Q from C to D, along the semicircle CD as shown in the figure below, is ______.

The period of oscillation of a body of mass m₁ suspended from a light spring is T. When a body of mass m₂ is tied to the first body and the system is made to oscillate, the period is 2T. Compare the masses m₁ and m₂

A 20 cm wide thin circular disc of mass 200 g is suspended to rigid support from a thin metallic string. By holding the rim of the disc, the string is twisted through 60° and released. It now performs angular oscillations of period 1 second. Calculate the maximum restoring torque generated in the string under undamped conditions. (π³ ≈ 31)

Find the number of oscillations performed per minute by a magnet is vibrating in the plane of a uniform field of 1.6 × 10^-5 Wb/m². The magnet has a moment of inertia 3 × 10^-6 kg/m² and magnetic moment 3 A m².

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Figures (a) and (b) show two Amperean loops associated with the conductors carrying current I in the sense shown. The `oint vecB * vecdl` in the cases (a) and (b) are, respectively.

A proton enters a perpendicular uniform magnetic field B at origin along the positive x axis with a velocity v as shown in the figure. Then it will follow the following path. [The magnetic field is directed into the paper].

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A conducting thick copper rod of length 1 m carries a current of 15A and is located on the Earth's equator. There the magnetic flux lines of Earth's magnetic field are horizontal, with the field of 1.3 x 10^-4T, south to north. The magnitude and direction of the force on the rod, when it is oriented so that current flows from west to east are ______.

An alpha particle (the nucleus of helium atom) (with charge +2e) is accelerated and moves in a vacuum tube with kinetic energy = 10.00 MeV. On applying a transverse a uniform magnetic field of 1.851 T, it follows a circular trajectory of radius 24.60 cm. Obtain the mass of the alpha particle.

[charge of electron = 1.62 × 10^-19 C]

A magnetic needle is suspended freely so that it can rotate freely in the magnetic meridian. In order to keep it horizontal position, a weight of 0.2 g is kept on one end of the needle. If the pole strength of the needle is 20 Am, find the value of the vertical component of the Earth's magnetic field. (g = 9.8 ms^-2)

A magnetic needle placed in uniform magnetic field has magnetic moment of 2 x 10^-2 A·m², and a moment of inertia of 7 .2 x 10^-7 kg·m². It performs 10 complete oscillations in 6 s. What is the magnitude of the magnetic field?

Show that the root means the square speed of the molecules of a gas is directly proportional to the square root of the absolute temperature of the gas.  

Derive the expression for the average pressure of an ideal gas.

The science of measuring temperatures is called?

A group of objects that can form a unit which may have the ability to exchange energy with its surrounding is called what? 

On what basis a thermodynamic system can be classified?

Classify and explain the thermodynamic system. 

The maximum speed of a particle executing S.H.M. is 10 m/s and maximum acceleration is 31.4 m/s². Its periodic time is ______ 

A simple pendulum is inside a spacecraft. What will be its periodic time? 

The period of oscillation of the simple pendulum increases by 20 %, when its length is increased by 44 cm. find its initial length. 

A standing wave is produced on a string fixed at one end with the other end free. The length of the string _____.