2 points (d) The figure below shows how the activity of a sample of potassium -40
changes over time. Use the figure above to determine the half-life of
potassium-40. Half-life =
billion years
1200
1000
800
Mass of
sample 600
in mg
400
200
0
0.0 1.0
2.0 3.0 4.0 5.0 6.0 7.0 8.0
Time in billions of years
Your answer

Imagine an isolated positive point charge q (many times larger than the charge on a single proton). there is a charged particle a (whose charge is much smaller than charge q) at a distance from the point charge q. on which of the following quantities does the magnitude of the electric field created by charge q at particle a's position depend? check all that apply.the type of the charge on the charged particle athe relative orientation between q and a (while the distance between q and a is fixed)the specific location of the charged particle a (while the distance between q and a is fixed)the amount of the charge on the point charge qthe specific location of the point charge q (while the distance between q and a is fixed)the distance between the point charge q and the charged particle athe amount of the charge on the charged particle a