A 500. gram sample of nickle-63 has a half-life of 100. years and has decayed for 500. years. How much of the original 500. gram sample remains?

87.1 grams

574 grams

16,000 grams

15.6 grams

A 6.50-kg object is hung from the bottom end of a vertical spring fastened to an overhead beam. the object is set into vertical oscillations having a period of 3.20 s. find the force constant of the spring.

1. A psychologist exposes several lab animals to an enriched environment (toys to play with) and then compares their ability to run mazes to that of control animals. a). Hypothesis: b). Independent variable: c). Dependent variable:

How is psychology considered science

A circuit has a current of 2.4 A. The voltage is increased to 4 times its original value, while the resistance stays the same.

The equation E=mc^2 relates energy and. a. Force. b. Mass. c. Gravity. d. Work.

A 2.25-kg block is released from rest on a ramp of height h. when the block is released, it slides without friction to the bottom of the ramp, and then continues across a surface that is frictionless except for a rough patch of width 15.

Which of the following are steps for balancing chemical equations? Check all that apply. ] A. Multiply the reactants to get the products. B. Change subscripts. O C.

1. Why does the water vapour in clouds condense? 2. Explain why you can see clouds but not see the water vapour in the air

What are some similarities between electricity and gravity?

What's the difference between solids and liquids?