An electron in the n=7 level of the hydrogen atom relaxes to a lower energy level, emitting light of 1005 nm. part a what is the value of n for the level to which the electron relaxed? express your answer as an integer.

Convection cells in the mantle are believed to be the main cause of plate movements these convection cells transfer ___ which ultimately causes the friction drag of plates on earths crust A. Electricity B. Heat C. Lava D. Magnetism

Are sound waves transverse waves or longitudinal waves? Why?

What is the frequency of 20 mm microwaves? A) 100 MHz B) 400 MHz C) 15 GHz D) 73 GHz E) 98 GHz

An object has a kinetic energy of 275 j and a momentum of magnitude 25.0 kg · m/s. find the (a) speed and (b) mass of the object.

during a crash, an airbag inflates to stop a dummys forward motion. the dummy mass is 75 kg. if the net force is on the dummy is 825 N toward the rear of the car, what is the dumys deceleration

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 ...