When the air under the envelope is heated, the balloon lifts. which of the following statements is true? a) hot air balloons use radiation to rise b) hot air balloons use conduction to rise c) hot air balloons use convection to rise d) hot air balloons use air resistance to rise

Adiver in midair has an angular velocity of 6.0 rad/s and a moment of inertia of 1.2 kg·m2. he then pulls is arms and legs into a tuck position and his angular velocity increases to 12 rad/s. the net external torque acting on the diver is zero. what is his moment of inertia in the tuck position?

What is the fate of the electrons that interact with a specimen in an electron microscope?

What happens in a global convection cell