Q1. A child is sliding on a sled at 1.6 {rm m/s} to the right. You stop the sled by pushing on it for 0.80 {rm s} in a direction opposite to its motion. If the mass of the child and sled is 41 {rm kg}, what average force do you need to apply to stop the sled? Utilize the concepts of impulse and momentum.
Q2. The normal lens on a 35- camera has a focal length of 50.0. Its aperture diameter varies from a maximum of 50 () to a minimum of 2.0 ().
Determine the resolution limit set by diffraction for and. state as the number of lines per millimeter resolved on the film.