Physics Test 92...

A Carnot heat engine has an efficiency of 10%. If the same engine is worked backward to obtain a refrigerator then find its coefficient of performance :-

Heat energy absorbed by a system in going through a cycle process shown in figure :-

Figure shows a composite slab of three different material a, b and c with equal thick and thermal conductivity K_a > K_b > K_c. The transfer of energy through them as heat is non-zero and steady. The temperature difference is the greatest across

Find the angle of deviation suffered by a ray incident on a plane mirror (as shown in figure) at an angle of incidence 30°.

With respect to air critical angle in a medium for light of red colour (λ₁) is θ. Other facts remaining same critical angle for light of yellow colour (λ₂) will be :

The radius of curvature of a convex spherical mirror is 1.2 m. How far away from the mirror is an object of height 1.2 cm be placed if the distance between its virtual image and the mirror is 0.3 m ?

In the given figure an observer in air (n = 1) sees the bottom of a breaker filled with water (n = 4/3) upto a height of 40 cm. What will be the depth felt by this observer.

A prism (n = 2) of apex angle 90° is placed in air (n = 1). What should be the angle of incidence if that light ray strikes the second surface at an angle of incidence 60°.

An object is placed at a distance of 20 cm in rarer medium, from the pole of a convex spherical refracting surface of radius 10 cm. If refractive index of rarer medium is 1 and of other medium is 2 then find position of image.

A biconvex lens with equal radii of curvature has refractive index 1.6 focal length 10cm. Its radius of curvature will be