Which type of force holds galaxies together?

Some waves do not need a medium such as

What is the speed of a wave if the wavelength is 3 meters and the frequency is 200 hertz

Which situation involves an object that can be considered to be in free fall? A) a bungee jumper just before reaching the bottom of a jump. B) a ball at the top of its motion after being thrown straight up in the air.

Which explains why the sky appears blue on a sunny day? A. Colors of light with longer wavelengths scatter too far for the eye to detect. B. Blue light scatters in all directions more than other colors of light. C.

When jogging outside you accidentaly bumb into a curb. Your feet stop but your body continues to movr foward and you end up on the ground. Which law of motion is being described in this scenario? A. Law of universal gravitation B.

When blue light of wavelength 450 nm falls on a single slit, the first dark bands on either side of center are separated by 45.0

An object is moving east, and its velocity changes from 65 m/s to 25 m/s in 10 seconds. Which describes the acceleration? 4 m/s2 in negative acceleration 4 m/s2 in positive acceleration 9 m/s2 in positive acceleration 9 m/s2 in negative acceleration

Two students walk in the same direction along a straight path at a constant speed-one at 0.90 m/s and the other at 1.90 m/s. •How far would the students have to walk so that the faster student arrives 5.50 min before the slower student? A.) 460s B.

During the process of accretion, each planet-in-the-making, or proto-planet, grew in size and mass. The amount of gravity for the proto-planets is best represented by which graph?

Theories and Laws. • How are they alike? • How are they different? • Can you explain why scientific theories will change over time? • Give an example of a scientific theory that has changed.