Fossil fuels can be replaced. Yet, they are considered
nonrenewable. Why?
A. Fossil fuels only take a few years to
replenish.
& Dirt
al
B. Fossil fuels take millions of years to
replenish.
C. Fossil fuels can never be replenished.
Silt

Determine the amount of work done when a crane lifts a 100-n block form 2m above the ground to 6m above the ground

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?