x-axis is normal to the reflecting surface of a plane mirror. If object is moving with velocity m/sec. The relative velocity of image with respect to object will be along
1. –x axis
2. +x axis
3. –z axis
4. +z axis
A simple telescope, consisting of an objective of focal length 30 cm and a single eye lens of focal length 6 cm. Eye observes final image in relaxed condition. If the angle subtended on objective is 1.5º then image will subtend angle of
1. 6.5º
2. 7.5º
3. 0.3º
4. 2.5º
When an object is placed at a distance of 25 cm from a mirror, the magnification is m1. The object is moved 15 cm away with respect to the earlier position along principal axis, magnification becomes m2. If m1m2 = 4, the focal length of the mirror is
1. 10 cm
2. 30 cm
3. 15 cm
4. 20 cm
number of identical equilateral prisms are kept in contact as shown in figure. If deviation through a single prism is then consider the following statements (m is an integer).
(i) if ( = 2m) deviation through prisms is zero
(ii) if ( = 2m + 1),deviation through system of prisms is
(iii) if = 2m,deviation through system of prisms is
(iv) if = 2m + 1,deviation through system of prisms is zero
1. statements (i) and (iii) are true
2. statements (i) and (ii) are true
3. statements (i) and (iv) are true
4. statements (iii) and (iv) are true
A telescope of diameter 2m uses light of wavelength 5000 Å for viewing stars. The minimum angular separation between two stars whose image is just resolved by this telescope is
1. 4 × 10–4 rad
2. 0.25 × 10–6 rad
3. 0.31 × 10–6 rad
4. 5.0 × 10–3 rad
A microscope is focused on a needle lying in an empty tank. Now, the tank is filled with benzene to a height 120 mm. The microscope is moved 40 mm to focus the needle again. The refractive index of benzene is
1. 1.5
2. 2.5
3. 3.0
4. 4.5
Magnification of a compound microscope is 30. Focal length of eye-piece is 5 cm and the image is formed at a distance of distinct vision of 25 cm. The magnification of objective lens is
1. 6
2. 5
3. 7.5
4. 10
An object starts rotating from point P in clockwise direction between focus F and centre of curvature C of a concave mirror as shown in figure. Corresponding image will rotate in path:
1. 1
2. 2
3. 3
4. 4
The x-z plane separates two media A and B of refractive indices m1 = 1.5 and m2 =2. A ray of light travels from A to B. Its directions in the two media are given by unit vectors and . Then
1.
2.
3.
4.
The refractive index n of a medium within a certain region x> 0, y>0 changes with y till it aquires a value nmax. After it aquires the value nmax it remains constant. A light ray travelling in air along the x-axis, strikes the medium at a grazing angle and moves through the medium along a circular arc as shown in the figure. If angular deviation of the ray before it starts moving on a straight line is 600, then nmax is
1. 2
2.
3.
4.
An object of length 1 cm is placed on the principle axis of an equiconvex lens of radius 5 cm. Distance between the lens and object is 20 cm. Space between the lens and object is filled with medium of two different refractive indices 2 and 1 as shown in the figure. Refractive index is 1 on the left of the object and on the right side of the lens. Boundary of both medium is mid-way between the object and lens.
1. The image will be formed at distance of 7.5 cm from the optical centre of lens
2. The image will be formed at distance of 10 cm from the optical centre of lens
3. The image will be formed at distance of 15.0 cm from the optical centre of lens
4. The image will be formed at distance of 12.5 cm from the optical centre of lens
A cylinder is filled with a liquid of refractive index m. The radius of the cylinder is decreasing at a constant rate K. The volume of the liquid inside the container remains constant at V. The observer and the object O are in a state of rest and at a distance L from each other. The apparent velocity of the object as seen by the observer, (when radius of cylinder is r)
1.
2.
3.
4.
An object of mass m is moving with velocity towards a plane mirror kept on a stand as shown in the figure. The mass of the mirror and stand system is m. A head-on elastic collision takes place between the object and the mirror stand, the velocity of image before and after the collision is
1.
2.
3.
4.