Why are Crop circles circle? Why not square?

On a cold winter day when the temperature is - 20∘C, what amount of heat is needed to warm to body temperature (37 ∘C) the 0.50 L of air exchanged with each breath? Assume that the specific heat of air is 1020 J/kg⋅K and that 1.0 L of air has mass 1.

You throw a stone vertically upward with an initial speed of 6.4 m/s from a third-story office window. A) Find the speed of the stone just before it hits the ground. Hint: the time is 2.3 s

If it takes a ball dropped from rest 2.069 s to fall to the ground, from what height h was it released?

convert watts to hpThe headlights of a moving car draw about 9 A from the 12 V alternator, which is driven by the engine.

A person pulls a cart with a force of 10n a distance of 8m how much work is done on this cart

Objects falling through the air experience a type of friction called air resistance. true or false

How big is a wifi pulse signal coming from your router? A) 10 meters B) 15 meters C) 5-10 meters D) 20-30 meters

Imagine you are in a music concert. What different sounds might you hear? How are these sounds made?

Dose aloe Vera grow in the mesa?

A tradesman sharpens a knife by pushing it against the rim of a grindstone. The 35 cm diameter stone is spinning at 200 rpm and has a mass of 28 kg. The coefficient of kinetic friction between the knife and the stone is 0.20.