A skydiver opens his parachute 45 seconds into his fall. He experiences an average acceleration of 29.4m/s^2 upward before reaching a constant velocity of 5.6m/s downwards 90 seconds into his fall. What is the skydiver’s velocity when he opened his parachute?

Contrast the force of gravity between these pairs of objects a 1 kg mass and a 2 kg mass that are 1 m apart and two 2 kg masses that are 1 m apart

Emmy kicks a soccer ball up at an angle of 45° over a level field. she watches the ball's trajectory and notices that it lands, two seconds after being kicked, about 20 m away to the north. assume that air resistance is negligible, and plot the horizontal and vertical components of the ball's velocity as a function of time. consider only the time that the ball is in the air, after being kicked but before landing. take "north" and "up" as the positive ‑ and ‑directions, respectively, and use ≈10 m/s2 for the downward acceleration due to gravity.

The buildup of charges on an object is called