The half-life for a 100-gram sample of radioactive element X is 5 days. How much of element X remains after 10 days have passed?

A. 25 g

B. 100 g

C. 75 g

D. 50 g

Suppose that a pane of crown glass, with a refractive index of 1.52, is immersed in water, which has a refractive index of 1.33. A ray of light traveling in the water strikes the glass at 45° relative to the normal and travels through the pane.

When washing tableware in a three-compartment sink, the water should be at least

Two charged particles are fixed to an x-axis: Particle 1 of charge q1 = 2.1 x 10-8 C is at position x=20 cm and particle 2 of charge q2=-4.00 q1 is at position x = 70 cm.

How does the size of the nucleus compared to the size of an atom

Wave A has an amplitude of 2, and wave B has an amplitude of 2. What will happen when the crest of wave A meets the trough of wave B?

A student is trying to calculate the density of a ball. She already knows the mass, but she needs to determine the volume as well. Which of the following formulas can be used to calculate the volume of the ball?

Is there such a thing as real time weather radar? why not?

Luke and Carrie are driving down a straight section of the interstate at 70 mph in Luke's new convertible. Carrie is drinking a soda in the passenger seat.

A force produces power p by doing work w in a time t. what power will be produced by a force that does six times as much work in half as much time?

A batter hits a baseball with a bat. The bat exerts a force on the ball. Does the ball exert a force on the bat?