# A rod of length 5 cm lies along the principal axis of the concave mirror of focal length 15 cm in such a way that the end of the rod which is closer to the pole is 30 cm away from it. Then the length of the image (a) 2.75 cm (b) 3.75 cm (c) 4.75 cm (d) None of these

## Question ID - 101080 :- A rod of length 5 cm lies along the principal axis of the concave mirror of focal length 15 cm in such a way that the end of the rod which is closer to the pole is 30 cm away from it. Then the length of the image (a) 2.75 cm (b) 3.75 cm (c) 4.75 cm (d) None of these

3537

3.75 cm

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 In each situation of Column I, uniform disc of mass and radius rolls on a rough fixed horizontal surface as shown. At (initially) the angular velocity of the disc is and velocity of the centre of mass of the disc is (in horizontal direction). The relation between and for each situation and also initial sense of rotation is given for each situation in column I. Then match the statements in Column I with the corresponding results in Column II
 Column-I Column- II (A) (p) The angular momentum of the disc about point A (as shown in the figure) remain conserved (B) (q) The kinetic energy of the disc after it starts rolling without slipping is less than its initial kinetic energy (C) (r) In the duration disc rolls with slipping, the friction acts on the disc towards the left (D) (s) In the duration disc rolls with slipping, the friction acts on the disc for some time to the right and for some time to the left CODES : A B C D a) C d b a b) a,c d,c c,d c,d c) b,a b,c d a,c d) a,b,c a,b,c a,b a,b,c 