Helium is used in balloons because it is

An object traveling at constant speed v in a circle of radius R has an acceleration am 5 m/s2. If both R and v are doubled, what is the new acceleration? 40 m/s2 10 m/s2 2.5 m/s? 5 m/s2

A car radio draws 0.18 A of current in the autos 12-V electrical system. (a) How much electric power does the radio use? (b) What is the effective resistance of the radio?

A person is pushing (and slightly squashing) a basketball against a wall. According to Newton's Third Law, the reaction force for the force that the hand exerts on the basketball is the force that the the force that the basketball exerts on the wall.

Newton's second law A. describes how an object accelerates when a force is applied B. says that objects eventually stop unless a force is applied C. objects with mass attract each other D. forces come in action/reaction pairs E.

How do galaxies vary?

What resultant force is needed to accelerate a train of mass 3.41000000 kg from rest to 15.0ms in exactly 20s

I to fall in love with someone or to at least get a boyfriend

Is rain falling a contact or noncontact force

How does a concave lens differ from a convex lens?

Which object has the greatest gravitational attraction?