What is the kinetic energy of a 59.1 kg man running along at 3.65 m/s?

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.