HSC Science (Computer Science) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

Two wires of the same material have radii rA and rB respectively. The radius of wire A is twice the radius of wire B. If they are stretched by same load then stress on wire B is _______.

If the total energy of radiation of frequency 10¹⁴ Hz is 6.63 J, calculate the number of  photons in the radiation. (Planck’s constant = 6.63 x 10^–34 J.s.)

The ratio of kinetic energy of an electron in Bohr’s orbit to its total energy in the same orbit  is

(A) – 1

(B) 2

(C) 1/2

(D) – 0.5

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 parallel beam of light travelling in water is incident obliquely on a glass surface. After refraction its width ..............

a) decreases

b) increases

c) remains the same

d) becomes zero

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

Determine the change in wavelenght of light during its passage from air to glass, if the refracrtive index of glass with respect to air is 1.5 and the frequency of light is 5 x 10¹⁴ Hz. Find the wave number of light in glass (velocity of light in air c = 3 X 10⁸ m/s)

What is electromagnetic induction?

What is electromagnetic induction?

Prove theoretically  (electromagnetic induction) `e = (dphi)/(dt)`

Prove theoretically  (electromagnetic induction) `e = (dphi)/(dt)`

Answer in brief:

Derive an expression for the period of motion of a simple pendulum. On which factors does it depend?

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

The minimum angular separation between two stars is 4 × 10⁻⁶ rad, if telescope is used to observe them with an objective of aperture 16 cm. Find the wavelength of light used.

If ‘R’ is the radius of dees and ‘B’ be the magnetic field of induction in which positive charges (q) of mass (m) escape from the cyclotron, then its maximum speed (vmax) is _______.

A) `(qR)/(Bm)`

B)`(qm)/(Br)`

C) `(qBR)/m`

D) `m/(qBR)`

If ‘R’ is the radius of dees and ‘B’ be the magnetic field of induction in which positive charges (q) of mass (m) escape from the cyclotron, then its maximum speed (vmax) is _______.

A) `(qR)/(Bm)`

B)`(qm)/(Br)`

C) `(qBR)/m`

D) `m/(qBR)`

Obtain an expression for magnetic induction along the axis of the toroid.

If the source is moving away from the observer, then the apparent frequency _____.

(a) will increase

(b) will remain the same

(c) will be zero

(d) will decrease

The compressibility of a substance is the reciprocal of _________.

(a) Young’s modulus

(b) bulk modulus

(c) modulus of rigidity

(d) Poisson's ratio

In interference pattern, using two coherent sources of light; the fringe width is ________

(a) directly proportional to the wavelength

(b) inversely proportional to the square of the wavelength

(c) inversely proportional to wavelength.

(d) directly proportional to the square of the wavelength.