What does H-R diagram stand for?

Will water flow more easily through a wide pipe or a narrow pipe? Will current flow more easily through a thick wire or a thin wire?

What beat frequencies result if a piano hammer hits three strings that emit frequencies of 392.0, 587.3, and 146.8 hz? (enter your answers from smallest to largest.) ?

Why do some elements have symbols that don't use letters in the element's name?

A cart of mass 0.400 kg moves with a speed of 1.2 m/s toward a secondary cart of mass 0.300 kg that is initially at rest. When the carts collide they stick together. What speed do the carts move with after the collision

An uncharged 1.0-μF capacitor is connected in series with a resistor, an ideal battery, and an open switch. What is the voltage across the capacitor after closing the switch?

8. A gas is contained in a horizontal piston-cylinder apparatus at a pressure of 350 kPa and a volume of 0.02 m3. Determine the work done by the piston on the gas if the cylinder volume is increased to 0.15 m3 through heating.

A 75.0 kg person stands on a scale in an elevator. (a) What does the scale read (in N and in kg) when the elevator is at rest?

The hinge at A and cable BDC support beam ABC. Cable BDC passes over the pulley D that is pinned to the ceiling. (Assume that the + x-axis is to the right and the + y-axis is up along the page.

The "zone of avoidance" a) Accounts for the absence of any planet between the orbits of Mars and Jupiter Prevents collisions between planets in the Solar System.

Electric current is ...