Why does a partially inflated balloon expand as it rises?

How did you measure viscosity in the lab?

A soccer player extends her lower leg in a kicking motion by exerting a force with the muscle above the knee in the front of her leg. Suppose she produces an angular acceleration of 29.5 rad/s2 and her lower leg has a moment of inertia of 0.95 kg⋅m2.

Which substance has the highest density at room temperature? a. hydrogenc. waterb. oxygend. they are all the same

A source emits sound with a frequency of 16246 Hz. Both it and an observer are moving toward each other, each with a speed of 141 m/s. What frequency (in Hz) does the observer hear?

If F1 = 390 N and F2 = 550 N, determine the angle θ (0∘≤θ≤180∘) between them, so that the resultant force has a magnitude of FR = 780 N. Express your answer to two significant figures and include the appropriate units.

A plane is flying east at 135 m/s. The wind accelerates it at 2.18 m/s^2 directly northeast. After 18.0s, what is the magnitude of the displacement of the plane?

The same constant force, F, is applied to two blocks. The first block has a mass of M and the second block has a mass of 2M. Both blocks are initially at rest and the force acts on each of them for the same period of time, t.

Which of the following is an example of the strong nuclear force acting in an atom? A. A proton repelling a proton B. A neutron attracting a neutron C. A neutron repelling an electron D. An electron attracting a proton

Does the air in our atmosphere have mass?

Your instructor hands you a closed flask partly filled with room-temperature water. When you hold it, the heat transfer between your bare hands and the flask causes the water to boil. Quite impressive! How is this accomplished?