What causes a bolt of lightning?
question options:
electrical charges build up in the clouds.
electrical charges build up on the ground.
electrical charges build up in the clouds and on the ground.
electrical charges build up in the space between the clouds and the ground.

Find the momentum for a 2.6-kg brick parachuting straight downward at a constant speed of 8.4 m/s .

An important dimensionless parameter concerned with very high-speed flow is the mach number, defined as v/c, where v is the speed of the object such as an airplane or projectile, and c is the speed of sound in the fluid surrounding the object. for a projectile traveling at 1170 mph through air at 50 ˚f and standard atmospheric pressure, what is the value of the mach number?

(a) if the pressure in gas is doubled while its volume is held constant, by what factor do (i) vrms and (ii) change? (b) is it possible to boil water at room temperature (20oc) without heating it? explain.