An electron e with kinetic energy 1.000 mev makes a head-on collision with a positron e at rest. (a positron is an antimatter particle that has the same mass as the electron but opposite charge.) in the collision the two particles annihilate each other and are replaced by two photons of equal energy, each traveling at angles θ with the electron's direction of motion. the reaction is show that the angle is cos θ--il a) c lity

The discovery that the universe appears to be expanding led to a widely accepted theory called a.) the big bang theory b.) the doppler effect c.) hubble’s law d.) solar nebular theory e.) the seyfert theory

What is a carrier wave and how does it affect what you hear on the radio

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f