HSC Science (General) इयत्ता ११ वी - Maharashtra State Board Question Bank Solutions

A concave mirror of curvature 40 cm, used for shaving purposes produces image of double size as that of the object. Object distance must be ______.

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As per recent development, what is the nature of light? Wave optics and particle nature of light are used to explain which phenomena of light respectively?

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Range of temperature in a clinical thermometer, which measures the temperature of the human body, is

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A glass bottle completely filled with water is kept in the freezer. Why does it crack?

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If two temperatures differ by 25° C on Celsius scale, the difference in temperature on Fahrenheit scale is

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If α, β and γ are coefficients of linear, area l and volume expansion of a solid then

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Consider the following statements-

(I) The coefficient of linear expansion has dimension K^-1.

(II) The coefficient of volume expansion has dimension K^-1.

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Water falls from a hight of 200 m. What is the difference in temperature between the water at the top and bottom of a waterfall given that the specific heat of water is 4200 J kg^-1 °C-1?

Solve Numerical example.

A monochromatic ray of light strike the water (n = 4/3) surface in a cylindrical vessel at angle of incidence 53°. Depth of water is 36 cm. After striking the water surface, how long will the light take to reach the bottom of the vessel? [Angles of the most popular Pythagorean triangle of sides in the ratio 3:4:5 are nearly 37°, 53°, and 90°]

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Electric conduction through a semiconductor is due to:

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What is the importance of the energy gap in a semiconductor?

Distinguish between action spectrum and absorption spectrum.

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Why is photolysis of water accompanied with non-cyclic photophosphorylation?

Define emissive power and coefficient of emmision of a body.

A metal sphere cools at the rate of 4°C / min. when its temperature is 50°C. Find its rate of cooling at 45°C if the temperature of surroundings is 25°C.

Two copper spheres of radii 6 cm and 12 cm respectively are suspended in an evacuated enclosure. Each of them are at a temperature 15°C above the surroundings. The ratio of their rate of loss of heat is.................

1. 2:1
2. 1:4
3. 1:8
4. 8:1

The dimensions of emissive power are ______.

A pinhole is made in a hollow sphere of radius 5 cm whose inner wall is at temperature 727^oC. Find the power radiated per unit area. [Stefan’s constant σ = 5.7 x 10^-8 J/m² s K4 , emissivity (e) = 0.2]

Compute the temperature at which the r.m.s. speed of nitrogen molecules is 832 m/s. [Universal gas constant, R = 8320 J/k mole K, molecular weight of nitrogen = 28.]

The light from the Sun is found to have a maximum intensity near the wavelength of 470 nm. Assuming the surface of the Sun as a black body, the temperature of the Sun is _____________.

[Wien's constant b = 2 .898 x l0^{- 3}mK]