A black hole is a star that has

begun to collapse in on itself

too little gravity to emit light

gotten to the middle of its life

become too bright to see

How might a nation be affected if another nation did not follow agreed upon water rules

Which happens to the magnetic field of a wire when you change the direction of the current in the wire? It becomes stronger. It becomes weaker. It changes direction too. It stays the same.

A wave has a speed of 50 m/sec. If its frequency is 100 Hz, what is its wavelength? Dis placement vs. Position

Which is the best example of refraction

The energy releasing process that breaks down large molecules into smaller ones is what?

The national grid supplied a house with 18000000 J of energy in 1 hour. What was the average current supplied to the house in that hour? Write any equations that you use.

Claudia throws a baseball to her dog. Which free-body diagram shows the baseball when it's flying horizontally in midair? (Assume no air resistance.)

Which of the following substances will show the smallest change in temperature when equal amounts of energy are absorbed? water air sand concrete

The downward acceleration of a falling body on Earth is 9.81m/s2. On the moon the same quantity is 1.62m/s2. An astronaut in a space suit has a mass of 145kg.

Explain how a guitar produces sound by using the terms standing waves and resonance.