Aspherical weather balloon is filled with hydrogen until its radius is 4.40 m. its total mass including the instruments it carries is 19.0 kg. (a) find the buoyant force acting on the balloon, assuming the density of air is 1.29 kg/m3. kn (b) what is the net force acting on the balloon and its instruments after the balloon is released from the ground? kn (c) why does the radius of the balloon tend to increase as it rises to higher altitude?

Write maxwell's equations and discuss the terms involved and the results of each equation in classical electrodynamics. if it is possible to write these equations in integral form, give the integral forms. find the wave equation for electromagnetic waves from the maxwell equations. what is the propagation velocity of electromagnetic waves in space according to the wave equation you find?

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?

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)