# Light reflection and refraction Worksheet-30

Light reflection and refraction Worksheet-30

1. The focal length of the concave mirror in the experimental set-up shown below is equal to A. 12.2 cm         B. 11.4 cm                   C. 11.0 cm                   D. 9.8 cm

1. On regular reflection from the surface XY, the reflected ray will go along: A. A                     B. B                     C. C                     D. D

1. By focusing the concave mirror to reflect sunlight towards a point at a distance ‘x’, skin burn is sensed. The distance x is equal to

A. f                      B. 2f                    C. f/2                  D. 3f/2

1. If a cardboard is placed (close to the mirror) to cover half the size of the concave mirror, the image formed will be

A. Complete                                   B. Brighter

C. Dimmer                                     D. Complete and dimmer

1. Which of the following cases is/are correct

A. B. C. D. 1. An object moves a distance 'f between 2f and f of a concave mirror. The image would have travelled a distance of

A. f                      B. 2f                    C. f/2                  D. infinity

1. Who among the following uses a concave mirror?

A. Automobile rider                     B. Shop-keeper

C. Dentist                                       D. All of these

1. In solar cookers, the type of mirror used as a concentrator is

A. Plane                                          B. Concave

C. Convex                                       D. Either plane or convex

1. If parallel beams, non-parallel to principal axis fall on the convex lens, they converge at a point

A. On principal axis                     B. Away from principal axis

C. Centre of curvature                 D. Called focus on the axis

1. Focal length of a convex lens is taken as

A. Positive

B. Negative

C. Positive or negative depending on object distance

D. Positive or negative depending on image distance