PLEASE HELP A particle travels in a circle of radius 76 cm and completes one revolution in 4.5 s. What is the centripetal acceleration of the particle?

A. 2.8 m/s2

B. 1.5 m/s2

C. 0.97 m/s2

D. 3.3 m/s2

28. a stone is projected at a cliff of height h with an initial speed of 42.0 mls directed at angle θ0 = 60.0° above the horizontal. the stone strikes at a, 5.50 s after launching. find (a) the height h of the cliff, (b) the speed of the stone just before impact at a, and (c) the maximum height h reached above the grou

The momentum of an isolated system is conserved a) only in inelastic collisions. b) only in elastic collisions. c) in both elastic and inelastic collisions

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?