A chair of mass 11.5 kg is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force F = 42.0 N that is directed at an angle of 38.0 below the horizontal and the chair slides along the floor.

*Use Newton's laws to calculate the normal force that the floor exerts on the chair.

A150 w lamp emits light of wavelength 590 nm uniformly in all directions. what is the photon flux (photons per unit area per unit time) on a small screen at a distance 2.3 m from the lamp? assume the photons are uniformly distributed over the surface of a sphere of radius 2.3 m.

Ais useful when you need a simple machine to you separate two things. a. lever b. screw c. pulley d. wedge

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.