If calvin pushes a lawnmower 20 meters with a force of 2n. how much work has he done?

where do supermassive black holes likely exist? A. at the center of the solar system B. inside gas giants planets C. at the center of galaxies D. all of the above E. none of the above

If 48 cm of brick and 15 cm of fiberglass have the same R value, then ... both materials have the same density both materials have the same insulating ability both materials have the same conducting ability both materials have the same mass

Sound with frequency 1240 Hz leaves a room through a doorway with a width of 1.13 m. At what minimum angle relative to the centerline perpendicular to the doorway will someone outside the room hear no sound?

32. In Fiji, the firewalkers perform on pumice after going into a cataleptic trance. Why is pumice especially suitable?

What allows the bimetallic coil to turn on or off a heating or cooling system? The two metals contract the same amount. The thermostat is set at a particular temperature. The two metals expand differently. The coil comes in contact with air.

At the beach, describe where or when you would see wave fronts. How are wave fronts useful to surfers?

How would the moon appear from earth if the moon did not rotate?

Block B has mass 4.00 kg and sits at rest on a horizontal, frictionless surface. Block A has mass 2.00 kg and sits at rest on top of block B. The coefficient of static friction between the two blocks is 0.400.

T=2π√ (l/g) is dimensionally correct

A penny falls from a windowsill which is 25.0 m above the sidewalk. How much time does a passerby on the sidewalk below have to move out of the way before the penny hits the ground?