HSC Science (Computer Science) 12th Standard Board Exam - Maharashtra State Board Important Questions for Physics

The energy of the free surface of a liquid drop is 5π times the surface tension of the liquid. Find the diameter of the drop in C.G.S. system.

A sonometer wire vibrates with frequency n₁ in air under suitable load of specific gravity of . When the load is immersed in water, the frequency of vibration of wire n₂ will be .........

What is the decrease in weight of a body of mass 600kg when it is taken in a mine of depth 5000m?

[ Radius of earth = 6400km, g = 9.8 m/s² ]

The dimensions of universal gravitational constant are........................

a. [L¹M⁰T⁰]

b. [L²M¹T⁰]

c. [L^-1M¹T^-2]

d. [L³M^-1T^-2]

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)

Calculate the period of revolution of Jupiter around the Sun. The ratio of the radius of Jupiter’s orbit to that of the Earth’s orbit is 5.

(Period of revolution of the Earth is 1 year)

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

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

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.

Determine the binding energy of satellite of mass 1000 kg revolving in a circular orbit around the Earth when it is close to the surface of Earth. Hence find kinetic energy and potential energy of the satellite. [Mass of Earth = 6 x 10²⁴ kg, radius of Earth = 6400 km; gravitational constant G = 6.67 x 10-11 Nm² /kg2 ]

A stone of mass 100 g attached to a string of length 50 cm is whirled in a vertical circle by giving velocity at lowest point as 7 m/s. Find the velocity at the highest point. [Acceleration due to gravity = 9.8 m/s2 ]

Find the total energy and binding energy of an artificial satellite of mass 800 kg orbiting at a height of 1800 km above the surface of the earth.

[G = 6.67 x 10^-11 S.I. units, Radius of earth : R = 6400 km, Mass of earth : M = 6 x 10²⁴ kg]

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.

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

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

'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 ]

Explain the rise of liquid in the capillary on the basis of pressure difference.

The escape velocity of a body from the surface of the earth is 11.2 km/s. If a satellite were to orbit close to the surface, what would be its critical velocity?