Two students drop an object into sand from a height of 1.5 meters. They record the depth of the hole made in the sand by each student’s object. What is the most likely explanation for the results?

When the velocity of an object is doubled, by what factor is its momentum changed? by what factor is its kinetic energy changed? a) the momentum is zero. b) the momentum is not zero. c) difficult to say.

Which of the following are considered noble gases? a. bromine b. neon c. argon d. chlorine

What are similarities and differences between refraction, reflection, diffraction and absorption?