A light-year is a unit of

a. time.

c. mass.

b. distance.

d. density.

Stars release lots of energy in the form of what kind (or kinds) of light? A. visible only B. invisible only C. both visible and invisible

A satellite of mass m takes time t to orbit a planet. if the satellite had twice as much mass, the time for it to orbit the planet would be:

An atom that changes so that it has an electrical charge is a (n)

How does the temperature of the Earth's mantle compare to the other layers of the Earth? A) The mantle is hotter than the core. B) The mantle is hotter than the crust. C) The mantle is the same temperature as the core.

Moore's Law postulates that: a. the number of transistors per square inch on integrated circuits will double every two years. b. a paradigm shift will take place in the technical sciences every two years. c.

Which are the most common producers in aquatic ecosystems? a - bacteria b - algae c - fish d - plants

You push a piano 5 meters across the floor with a force of 400 n. how much work have you done?

Monochromatic electromagnetic radiation illuminates an area of a surface. The electric and magnetic fields of the waves are then doubled in magnitude.

The measure of the force of gravity on an object, expressed as mass of the object times acceleration due to gravity is called

Which of the following jobs does not require good swimming ability