Coulomb's Law: Coulomb's law is F = k (q1xq2)/ r^2 where k = 9 x 10^9 C^2/m^2. a) Sketch the charges and use Coulomb's law to determine the electric force between two charged particles where q1 = -5 x 10^-3 C and q2 = -1 x 10^-3 C. Q1 and Q2 are separated by a distance of 0.25 m. b) Determine whether the electric force attractive or repulsive and explain your answer?

Askydiver weighing 140 lb (including equipment) falls vertically downward from an altitude of 19,000 ft and opens the parachute after 18 s of free fall. assume that the force of air resistance, which is directed opposite to the velocity, is of magnitude 0.55|v| when the parachute is closed and is of magnitude 14|v| when the parachute is open, where the velocity v is measured in ft/s. assume that acceleration due to gravity has magnitude 32 ft/s/s; remember that weight is the product of mass and gravitational acceleration. (a) find the speed of the skydiver when the parachute opens. (b) find the distance fallen before the parachute opens. (c) what is the limiting velocity vl after the parachute opens? (d) determine how long the sky diver is in the air after the parachute opens. (e) plot the graph of velocity versus time from the beginning of the fall until the skydiver reaches the ground.

You are about to open a container of soy milk but notice that there are instructions to “shake well before serving.” the soy milk is most likely a

When you jump from an elevated position you usually bend your knees upon reaching the ground. by doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. in this way the average force your body experiences is a) less than 1/10 as great. b) more than 1/10 as great. c) about 1/10 as great. d) about 10 times as great.