HSC Science (General) इयत्ता १२ वी - Maharashtra State Board Question Bank Solutions

The surface tension of water at 0°C is 75.5 dyne/cm. Calculate surface tension of water at 25°C.

(α for water = 2.7×10^-3/°C)

Derive an expression for excess pressure inside a drop of liquid.

If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be ______.

A circular coil of 300 turns and average area 5 * 10^-3m² carries a current of 15A. Calculate the magnitude of magnetic moment associated with the coil.

Angle of contact for the pair of pure water with clean glass is _______.

The equation of a progressive wave is y = 7 sin (4t - 0.02x), where x and y are in cms and time t in seconds. The maximum velocity of a particle is _______.

The fundamental frequency of transverse vibration of a stretched string of radius r is proportional to _______.

A raindrop of diameter 4 mm is about to fall on the ground. Calculate the pressure inside the raindrop. [Surface tension of water T = 0.072 N/m, atmospheric pressure = 1.013 x 10⁵ N/m² ]

Draw a neat labelled diagram showing forces acting on the meniscus of water in a capillary tube.

A rectangular coil of a moving coil galvanometer contains 50 turns each having area 12 cm2 . It is suspended in radial magnetic field 0.025 Wb/m² by a fibre of twist constant 15 x10^-10 Nm/degree. Calculate the sensitivity of the moving coil galvanometer.

Define the angle of contact.

Water rises to a height 3.2 cm in a glass capillary tube. Find the height to which the same water will rise in another glass capillary having half area of cross section.

The average displacement over a period of S.H.M. is ______.

(A = amplitude of S.H.M.)

In which of the following substances, surface tension increases with increase in temperature ?

1. Copper
2. Molten copper
3. Iron
4. Molten iron

Define phase of S.H.M.

Show that the current flowing through a moving coil galvanometer is directly proportional to the angle of deflection of coil.

Write the underlying principle of a moving coil galvanometer.

'n' droplets of equal size of radius r coalesce to form a bigger drop of radius R. The energy liberated is equal to...................

(T =Surface tension of water)

`(a) 4piR^2T[n^(1/3)-1]`

`(b) 4pir^2T[n^(1/3)-1]`

`(c) 4piR^2T[n^(2/3)-1]`

`(d)4 pir^2T[n^(2/3)-1]`

The surface tension of water at 0ºc is 75·5 dyne/cm. Find surface tension of water at 25°C. [ α for water = 0·0021/°C ]

The Earth is rotating with angular velocity ω about its own axis. R is the radius of the Earth. If Rω² = 0 · 03386 m/ s² , calculate the weight of a body of mass 100 gram at latitude 25°.   (g=9·8m/s²).