If a sample that is 4860 years old has 50 radium atoms remaining, how many atoms were in the original sample?

1. Write 4 to 5 sentences about what Chapter 1 says about the early scientists from Aristotle to Galileo thought about the nature of motion. (Hint: Need to include Aristotle, Galileo, and Copernicus.

Howard is flying a kite and wants to find its angle of elevation. The string on the kite is 32 meters long and the kite is level with the top of a building that he knows is 28 meters high.

What formula is used to find acceleration?

The electric force on object A by object B is F. If the charge of object B were only half as large as it is, but everything else was kept the same, what would be the new electric force on object B by object A?

Why is it difficult to test the efficacy of biofeedback using experimental techniques? A. It is difficult to devise a control treatment that replicates biofeedback. B. Biofeedback cannot be subjected to testing because it is pseudoscience. C.

Explain why Planck's introduction of quantization accounted for the properties of black-body radiation.

How and which waves travel either through a medium or a vacuum?

Which of the following most accurately represents John Dalton's model of the atom?

A race car travels a circular track at an average rate of 135 mi/hr. The radius of the track is 0.450 miles. What is the centripetal acceleration of the car?

Between a substance and a mixture.