HSC Science (Computer Science) इयत्ता १२ वी - Maharashtra State Board Important Questions for Physics

A thin wire of length L and uniform linear mass density r is bent into a circular coil. M. I. of the coil about tangential axis in its plane is ................................

1. `(3rhoL^2)/(8pi^2)`
2. `(8pi^2)/(3rhoL^2)`
3. `(3rhoL^3)/(8pi^2)`
4. `(8pi^2)/(3rhoL^3)`

A body starts rotating from rest. Due to a couple of 20 Nm it completes 60 revolutions in one minute. Find the moment of inertia of the body.

The moment of inertia of a thin uniform rod of mass M and length L, about an axis passing through a point, midway between the centre and one end, perpendicular to its length is .....

(a)`48/7ML^2`

(b)`7/48ML^2`

(c)`1/48ML^2`

(d)`1/16ML^2`

A wheel of moment of inertia 1 Kgm² is rotating at a speed of 40 rad/s. Due to friction on the axis, the wheel comes to rest in 10 minutes. Calculate the angular momentum of the wheel, two minutes before it comes to rest.

Derive an expression for kinetic energy, when a rigid body is rolling on a horizontal surface without slipping. Hence find kinetic energy for a solid sphere.

A solid cylinder of uniform density of radius 2 cm has mass of 50 g. If its length is 12 cm, calculate its moment of inertia about an axis passing through its centre and perpendicular to its length.

Choose the correct option.

If the pressure of an ideal gas decreases by 10% isothermally, then its volume will ______.

A solid sphere of mass 1 kg rolls on a table with linear speed 2 m/s, find its total kinetic energy.

A uniform solid sphere has radius 0.2 m and density 8 x 10³ kg/m³. Find the moment of
inertia about the tangent to its surface. (π = 3.142)

If a rigid body of radius ‘R’ starts from rest and rolls down an inclined plane of inclination
‘θ’ then linear acceleration of body rolling down the plane is _______.

The body is rotating with uniform angular velocity (w) having rotational kinetic energy (E). Its angular momentum (L) is: ...............

a) `(2E)/ω`

b) `E^2/ω`

c) `E/ω^2`

d) `E/(2ω)`

A uniform solid sphere has a radius 0.1 m and density 6 x 103 kg/m3• Find its moment of inertia about a tangent to its surface.

A stone of mass 2 kg is whirled in a horizontal circle attached at the end of 1.5m long string. If the string makes an angle of 30° with vertical, compute its period. (g = 9.8 m/s²)

The kinetic energy of emitted photoelectorns is independent of ............

(a) frequency of incident radiation.

(b) intensity of incident radiation.

(c) wavelength of incident radiation

(d) collector plate potential

A ballet dancer spins about a vertical axis at 2.5Π rad/s with his both arms outstretched. With the arms folded, the moment of inertia about the same axis of rotation changes by 25%. Calculate the new speed of rotation in r.p.m.

If ‘L’ is the angular momentum and ‘I’ is the moment of inertia of a rotating body, then `L^2/(2I)`represents its _____

(A) rotational P.E.

(B) total energy

(C) rotational K.E.

(D) translational K.E

A thin ring has mass 0.25 kg and radius 0.5 m. Its moment of inertia about an axis passing through its centre and perpendicular to its plane is _______.

Define radius of gyration. Write its physical significance.

The radius of gyration of a body about an axis, at a distance of 0.4 m from its centre of mass is 0.5 m. Find its radius of gyration about a parallel axis passing through its centre of mass.