Astone is tossed into the air from the ground level with an initial velocity 15 m/sec. it’s height in meters a t seconds is h(t) = 1.5t - 4.9t^2. compute the average velocity of the stone over the given time intervals, then use that information to calculate the instantaneous velocity of the stone at t = 1sec. show your work time intervals:
a) [1, 1.0]
b) [1, 1.01]
c) [1, 1.005]
d) [1, 1.001]

Groups of organs that work together to complete a process in the body are called: a. cells b. tissues c. nerves d. systems

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?