Bill does 1500 j of work on a leaver, which is a simple machine. The lever does 1350 j of work on a stone. What is the efficiency of the leaver?

Which element has the greatest number of valence electrons? A. Silicon B. chlorine C. sodium D. magnesium

How do you measure mass

What is the difference between frequency and speed?

Explain what happens to the pitch of a cell phone ring when the wavelength of a sound wave increases

Shining a beam of light on a metal has no effect. What change would be most likely to cause the ejection of electrons from the metal. Choose all that apply. Group of answer choices Increase the intensity of the light.

If element X has 17 protons, how many electrons does it have?

A 2.0-kilogram laboratory cart is sliding across a horizontal frictionless surface at a constant velocity of 4.0 meters per second east. What will be the cart's velocity after a 6.0-newton westward force acts on it for 2.

A boat floats with 25% of its volume under water. a. What is the boatâs density? b. If the boat was made from 500 kg of metal, what is the volume of the boat? (Assume the air in the boat has negligible mass and density) c.

Why does each mineral have their own property, different from every other mineral?

Earth's tallest mountain ranges are found at plate boundaries