Asoccer player practices kicking the ball into the goal from halfway down the field the time it takes for the ball to get to the goal from the time it was kicked averages about 3 seconds the soccer field is 90 meters long the player wants to know the average velocity of the ball is there enough information to calculate this ?

In a popular classroom demonstration, solid sodium is added to liquid water and reacts to produce hydrogen gas and aqueous sodium hydroxide. part a write a balanced chemical equation for this reaction. express your answer as a chemical equation. identify all of the phases in your answer.

Asample of silver (with work function ? = 4.52 ev) is exposed to an ultraviolet light source (? = 200 nm), which results in the ejection of photoelectrons. what changes will be observed if: silver is replaced with copper (? = 5.10 ev) more photoelectrons ejected no photoelectrons are emitted fewer photoelectrons ejected more energetic photoelectrons (on average) less energetic photoelectrons (on average)

Which of the following methods uses the decay of atomic particles in an object to find its exact age? a. fossil dating b. geologic dating c. radioactive dating d. relative dating