The maximum wavelength of light required to eject an electron from zinc is 270nm. Calculate the threshold frequency of zinc.

Which of the following is true regarding current in an external circuit

Which two types of waves can transmit energy through a vacuum? 1. radio waves 2. seismic waves 3. sound waves 4. water waves 5. x-rays

What output force is generated when an input force of 630 n is applied to a machine with a mechanical advantage of 3

Hypothesis why would momentum not be conserved when 2 vehicles collide?

You throw a rock upwards; it rises and then falls back down. We know that the acceleration due to gravity is 9.8 m/sec2 near the surface of earth.

What is cosmic microwave background radiation?

Ocean water has a salinity of 35 parts per thousand. Fresh water has a salinity of less than 0.5 parts per thousand. What can you conclude from this information? A. Ocean water is rich in salt minerals. B.

You decide to add up all the work you did yesterday. If you accomplished 10,000 newton·meters of work yesterday, how much work did you do in units of joules?

What causes day and night on earth?

A yo-yo can be thought of as a solid cylinder of mass m and radius r that has a light string wrapped around its circumference (see below). One end of the string is held fixed in space.