How much larger is the required centripetal acceleration for a car rounding a curve at 60 mph than for one rounding the same curve at 20 mph?

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

In a vernier instrument the main scale is in 1/2 mm divisions .vernier is made by redividing 19 such divisions into 20 equal parts. calculate the least count of the instrument.

In a voltaic cell, electrons flow from the (positive/negative) to the (positive/negative) terminal.