Acouch with a mass of 80 kg is pushed with a force of 72 n to the right. friction exerts a force of 4 n to the left. the normal force and weight are 784 n in opposite directions. using a free-body diagram, determine the magnitude of the acceleration of the couch.

An automobile of mass 2000 kg moving at 30 m/s is braked suddenly with a constant braking force of 10000 n. how far does the car travel before stopping?

Prompta snowboarder stands at the top of a hill and decides to see if he can increase his speed on his next trip down the slope.describe one thing the snowboarder could do to incrlase his speed on the slope. explain why this would cause his speed toincrease relate one of newton's laws to this problem.

Light from a sodium lamp passes through a diffraction grating that has 1000 slits per millimeter. the interference pattern is viewed on a screen 1.000 m behind the grating. the first (m = 1) two bright yellow fringes that are visible are 0.7288 m and 0.7300 m from the central maximum. what are the wavelengths of these two fringes?