A person stands on a scale inside an elevator at rest (see the figure below). The scale reads W = 846 N. a (a) What is the person's mass? 86.268 kg (b) The elevator accelerates upward momentarily at the rate of a = 4 m/s2. what does the scale read then? X N (c) The elevator then moves with a steady speed of 4 m/s. What does the scale read now?

A skydiver weighing 203 lbf (including equipment) falls vertically downward from an altitude of 5000 ft and opens the parachute after 14 s of free fall. Assume that the force of air resistance, which is directed opposite to the velocity, is 0.77 |v| when the parachute is closed and 10 |v| when the parachute is open, where the velocity v is measured in ft/s. Use g = 32 ft/s². Round your answers to two decimal places. (a) Find the speed of the skydiver when the parachute opens. v(14) = i (b) Find the distance fallen before the parachute opens. x (14) = i ft ft/s (c) What is the limiting velocity after the parachute opens? UL = i ft/s

An elevator of mass 300 kg is caused to accelerate upward at 2.5 m/s2 by a force in the cable that supports it. What is the force exerted by the cable (in N) ?

A tractor is speeding up at 3 m/s/s while pulling a 744 kg sled with a rope at an angle of 34 degrees. The coefficient of kinetic friction between the sled and ground is 0.5. What is the tension (Newtons) in the rope? (g=9.8 m/s2)