Consider an elevator with a table and a book on top of the table. The mass of the table is 10kg and the mass of the book is 2kg. At t=0 the elevator is moving up with a velocity of 1m/s.
At t=2s the elevator is moving up with a velocity of 8 m/s

Find the Force from the Book to the Table in N. Use the convention where a positive value(+) means upward force and a negative value(-) means downward force.

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

Which is not true about oxygen-17 and oxygen-18?

Iwill give 30 points to whoever answers ! what is the formula for actual mechanical advantage and ideal mechanical advantage?