A sample of radioactive waste has a half-life of 10 years and an activity level of 2 curies. After how many years will the activity level of this sample be 0.25 curie?

Monarch butterflies can sustain air speeds of 4.8 m/s while migrating. A certain monarch wants to fly to a location due east 4.7 km away. A steady 2.4 m/s breeze is blowing from the west to the east.

In the study of sound, one version of the law of tensions is: f1 = f2 √ (F1/F2) If f1 = 300, F2 = 60, and f2=260, find f1 to the nearest unit.

How much greater is the shaking produced by a magnitude 8 earthquake than a magnitude 5 earthquake using the Richter Scale? a. 10,000 times greater b. 100 times greater c. 3,000 times greater d. 1,000 times greater

Organic chemistry is the study of compounds containing

Is average speed a scalar or vector quantity? why?

15 grams of liquid plastic are frozen in a physical change that increases the volume. What can be known about the plastic after the change?

A Car is lifted a certain distance in a service station and therefore has potential energy relative to the floor. if it was lifted twice as high, how much potential energy would it have?

How long does it take a 750-w coffeepot to bring to a boil 0.75 l of water initially at 11°c? assume that the part of the pot which is heated with the water is made of 280 g of aluminum, and that no water boils away?

An electric motor rotating a workshop grinding wheel at a rate of 151 rev/min is switched off. Assume constant angular deceleration of magnitude 2.23 rad/s 2. Through how many revolutions does the wheel turn before it finally comes to rest

1. What is the atomic number of an atom? Why is this number important? |