There is a 50 g sample of Ra-229. It has a half-life of 4 minutes.

How much will be left after 12 minutes?

A. 3.13 g

B. 6.25 g

C. 12.5 g

D. 25 g

Is the water in the us different than the water in Europe?

If a football player collides with a goal post, what forces are at work?

The dipole moment of HI is 0.42D. What is the dipole moment of HI in C⋅m?

Which city had many deaths from smog in 1952

A 50g mass of metal (c=0.20 cal/g°C) at 90°c is dropped into water at 30°c and the temperatures stabilized at 40°c. 100g 50g 2.0g 70g

Ways in conserving and preserving our water resources in our daily lives

A 1 cm^3 block with a density of 0.92 g/cm^3 is floating in a container of water (d = 1g / cm^3). You may ignore any air pressure throughout this problem. What buoyant force is necessary to keep the block from sinking?

F a thermometer is calibrated to the nearest degree, to what part of a degree can you estimate the temperature it measures?

Is a charge 5.8 * 10^-18 C possible?

If object A has half the mass of object B, but object A moves three times as fast as object B, which object has a greater momentum? Provide proof in your work.