- What are the five points in the Particle Theory?
- An unstable particle is at rest and suddenly breaks-up into two fragments. No external forces act on the particle or its fragments. One of the fragments has a velocity of +0.800c and a mass of 1.67times 10 {}^27kg while the other has a mass of 5.01times 10^-27kg What is the velocity of the more massive fragment?
- A lightweight material is being tested for effectiveness in blocking utraviolet (UV)rays from the Sun that cause skin to burn and possibly develop skin cancer. Which method would be most helpful for lesting this material? Use specialized equipment to measure how much UV light passes through stacks of one, five, or 20 layers of the material. Test the materialin controlled natural settings by using natural UV light, and measure the UV light that passes through. Write a survey that asks people on beaches about their preferences for sunscreen and protective materials. Test the material in a lab setting by using humans and a variety of UV light sources, and develop a scale to measure the damage that is caused to human skin.
- km, the nearest star, 15. How long will it take for light from Alpha Centauri to reach Earth? What could this mean?
- Four waves are to be sent along the same string, in the same direction: y_(1)(x,t)=(4.90mm)sin(2pi x-430pi t+0.42pi ) y_(2)(x,t)=(4.90mm)sin(2pi x-430pi t+0.93pi ) y_(3)(x,t)=(4.90mm)sin(2pi x-430pi t+1.42pi ) y_(4)(x,t)=(4.90mm)sin(2pi x-430pi t+1.93pi ) What is the amplitude of the resultant wave?
