How long would it take for a sound impulse to travel through a copper Rod 20km

Which statement is false? A. Isotopes have the same number of protons B. Isotopes have the same number of neutrons C. Isotopes have the same number of electrons

Which describes the properties reflection, absorption, and transmission when the light is shining on the oval end of a silver spoon? A. It reflects all lights, transmits all light, and absorbs some lights B.

If the volumes of the two rocks are equal the rock with the greater density has what

A submarine begins ascending to the surface of the ocean. It experiences an overall acceleration of 1.7m/s^2 for the first 5s. What is it's velocity after 3.2 s?

The basic building blocks of matter are called

In a laser, electrical energy is changed to light energy, and a small amount of the energy is wasted as heat. Describe the total amount of the heat in the system (using the conservation of energy).

What is the name for a star and planets held together by gravity? A. solar system B. galaxy C. black hole D. supernova

When a car turns a corner on a level road, which force provides the necessary centripetal acceleration? 1) gravity 2) normal force 3) air resistance 4) tension 5) friction

Use Newton's universal law of gravitation to explain why gravity is greater on Earth than on Mercury.

What is a magnetic field and how does it interact with magnetic materials?