Acyclist allows his bike to roll down a hill without pedaling . towards the bottom of the hill he applies his brakes. the bike comes to a stop. applying the brakes causes the brakes to warm up. describe the energy transfers that have occurred. state the forces doing work that couses each these energy transfers . you can ignore any friction between the bike and the ground and any air resistance.

What kind of waves require a medium to travel? question 6 options: light waves mechanical waves all waves need a medium to travel electromagnetic waves

You are the coordinator for a program that is going to take place at night in a rectangular amphitheater in the mountains. you will have no access to any electricity, but you must be able to illuminate the entire grounds. you know the intensity of the light from a lantern varies inversely as the square of the distance from the lantern. suppose the intensity is 90 when the distance is 5 m. a. write an equation to model the situation. b. solve for the constant of variation. c. write the equation to model the situation using the constant () of variation. d. you have been given lanterns with 40 light intensity. use your equation to solve for the distance from the lantern. e. you need to illuminate 225 km. how many meters do you need to light? f. how many lanterns will you need?

A60-gram sample of radioactive isotope is measured after two half-lives have passed. what pair of percentages describe the sample after two-half lives? a.) 50% unchanged and 50% stable b.) 25% unchanged and 75% stable c.) 12.5% unchanged and 87.5% stable d.) 75% unchanged and 25% stable