Which statement is true?

A. Some molecules may contain no atoms.

B. Some elements found in nature exist as molecules.

C. Some compounds include only one type of element.

D. Some atoms are made of two or more different elements.

Define, identify, and differentiate different forms of energy

Which type of wave cannot transmit energy through a vacuum

While goofing off at the ice skating rink, a student takes off her shoes and places each of them on the ice. Her friend, a hockey player, then shoots a hockey puck at each shoe.

For long-distance transmission of power, in order to reduce losses in the wires by driving a low current at high voltage, we should a) use a step-up transformer b) change the length of the wires between transmission towers c) not use a transformer

In a gas kept at a constant temperature, all molecules move with the same speed.

Describe and apply Newton's Three Laws

If you do 1000j of work on a system and remove 500j of heat from it, what is the change in its internal energy

Two children stretch a jump rope between them and send wave pulses back and forth on it. The rope is 4.5 m long, its mass is 0.42 kg, and the force exerted on it by the children is 71 N.

An object will only change its motion if a force is directly applied to it. is this a true statement?

Janice has just measured the density of an object. Which value is possible? (Density: D = )