Sr-90 has a half-life of T1/2 = 2.85 a (years). How much Sr-90 will remain in a 5.00 g sample after 5.00 a? Show all of your work. (2 marks)

tres cargas eléctricas cuyos valores son q1=3uc q2=-5uc y q3=-7uc de encuentran distribuidas en un triángulo. cuál es la magnitud de las fuerzas resultante sobré la carga q3 y su ángulo respecto a su eje horizontal

A cyclist rides her bike 7 mi east, and then 2 mi north before taking a break. Then she rides 5 mi east and then 3 mi north. What are the magnitude and direction of the cyclist's resultant displacement? magnitude: 13.0 mi; direction: 22.

In an experiment, a researcher can make claims about causation

Suppose you are in an elevator car when the elevator cable breaks. Which of the following correctly describes what happens and why. A. You float weightlessly within the elevator car because Earth's gravity is no longer tugging on you. B.

How can you use a graph to represent the motion of an object?

A new object has been discovered in the solar system. In your own words, justify how the object can be proved to be a comet.

What is cosmic microwave background radiation?

Ocean water has a salinity of 35 parts per thousand. Fresh water has a salinity of less than 0.5 parts per thousand. What can you conclude from this information? A. Ocean water is rich in salt minerals. B.

You decide to add up all the work you did yesterday. If you accomplished 10,000 newton·meters of work yesterday, how much work did you do in units of joules?

What causes day and night on earth?