Which best describes a reference frame?

A. a distance over which an object moves

B. the difference between start and end velocity

C. a position from which something is observed

D. the average speed of a group of objects

Im doing the BIg Bang for my project anyone know what it is, make it a ¨question¨ and an experiment.

How does the speed ratio change as you switch between different gears on a bicycle, and how does this affect the force you need to pedal the bicycle?

Name two conditions that are necessary for fusion to occur in the Sun's core.

What has four fingers and a thumb, but is not living?

A meter is measured in?

The locations of the major pressure and wind systems on the earth:

Which statements correctly describe the properties of heat? Select all that apply. Heat is an essential component of life on Earth. Heat is energy that flows from one object to another. Heat flows from a hotter object to a colder one.

A book is sitting on a table at rest. Which of the following best describes the forces acting on the book? A.

When NASA's Skylab reentered the Earth's atmosphere on July 11, 1979, it broke into a myriad of pieces. One of the largest fragments was a 1770-kg lead-lined film vault, and it landed with an estimated speed of 120 m/s.?

A spring gains 2.34 joules of elastic potential energy as it is compressed 0.250 meter from its equilibrium position. What is the spring constant of this spring? (1) 9.36 N/m (3) 37.4 N/m (2) 18.7 N/m (4) 74.9 N/m