a ray of light is incident in water at angle of 30 on water air plane mirror surface .find the angle of refraction in air.

What is the electric force acting between two charges of -0.0045 c and -0.0025 c that are 0.0060 m apart? use fe=kq1q2/r^2 and k = 9.00 x 10^9 n*m^2/c^2 a. 1.7 x 10^7 n b. -1.7 x 10^7 n c. -2.8 x 10^9 n d. 2.8 x 10^9 n

Asap and show ! a 14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.

Six pendulums of mass mand length las shown are released from rest at the same angle theta from vertical. rank the pendulums according to the numberof complete cycles of motion each pendulum goes through perminute. a. l= 1m m=2kg b. l= 4m m=1 kg c. l= 2 m m= 2 kg d. l= 1 m m= 4 kg e. l= 2 m m = 4 kg f. l= 4m m = 4kg