Q1. A box of books weighing 352 N moves with a constant velocity across the floor when it is pushed with a force of 448 N exerted downward at an angle of 30.7? below the horizontal.

Find μk between box and floor.

Q2. Find out the object position p for the image to be erect and 7 times the size of the object. Focal length is 46 cm

Q3. A 12.0-kg crate slides along a horizontal frictionless surface at a constant speed of 4.0m/s. the crate then slides down a frictionless incline and across a second horizontal surface. What is the speed of crate when it arrives at the lower surface, what is the kinetic energy of the crate as it slides on the lower surface, and what minimum coefficient of kinetic friction is necessary to bring crate to a stop over a distance of 9.0m along the lower surface?