What is the best alternative explanation for the dark matter in the milky way based on the observed orbital motions of stars and gas?

What color of light has the most energy? A. Blue B. Red C. Green

0.10-kilogram model rocket's engine is designed to deliver an impulse of 6.0 newton-seconds. If the rocket engine burns for 0.75 second, what average force does it produce?

Which change in state requires that energy be added to the substance Freezing deposition Condensing Vaporizing

Describe how momentum is calculated.

You are pushing a friend on a sled. You push with a force of 20N. Your friend and the sled together have a mass of 60kg. Ignoring friction, what is the acceleration of your friend on the sled?

How would you describe the two projectors used to screen a three-dimensional movie? A. Both projectors have vertical polarizers. B. One projector has a vertical polarizer and the other has a horizontal polarizer. C.

A roller coaster has a mass of 500 kg. It drops from rest at the top of a hill that's 57 m tall. How fast is it going when it reaches the bottom? Acceleration due to gravity is g = 9.8 m/s2.

Two sinusoidal waves are moving through a medium in the positive x-direction, both having amplitudes of 7.00 cm, a wave number of k=3.00m-1, an angular frequency of ω=2.50s-1, and a period of 6.00 s, but one has a phase shift of an angle ϕ=π12rad.

For a vacation, you and your family fly east to west from Boston, Massachusetts, to Seattle, Washington. You notice that your flight back home to Boston is shorter than your flight to Seattle. Which phenomenon causes your flight home to be shorter?

You spy on an anchor on the bottom of a lake. What is the direction and amount of force the water exerts on it: a) zero b) up, equal to the weight of the anchor. c) up, less than the weight of the anchor d) down, equal to the weight of the anchor.