Which of the following elements is an alkali metal?

Select one:

a. magnesium

b. sodium

c. calcium

d. mercury

At a hot air balloon race, a person on the ground shots a ball of confetti from a cannon to start the race. One of the balloons is rising with a constant speed of 11m/s. The confetti ball is shot completely verically with an initial speed of 18m/s.

Explain why a crack in glass looks brighter than the rest of the glass

What is the gravitational force acting on a 70.0 kg object standing on the earth's surface?

What are distinct layers caused by

The light from Star 1 reaches Star 3 in 138 years and Star 2 in 63 years. Which of these conclusions about the stars is correct? A. The distance between Star 2 and Star 3 is 75 light years. B.

How are energy and speed related

11. Which of the following best explains velocity? A. The direction of an object in motion B. Only the change of direction of an object in motion C. The speed and direction of an object in motion D. The speed of an object in motion

Using 6400 km as the radius of Earth, calculate how high above Earth's surface you would have to be in order to weigh 1/16th of your current weight. Show all work leading to your answer OR describe your solution using 3 - 4 complete sentences.

Which of these could occur if a switch is closed? A. A light bulb will light up. B. A hair dryer will turn off. C. A computer will shut down. D. B and C

When you throw a ball the work you do to accelerate it equals the kinetic energy the ball gains?