When did humans first learn that earth is not the center of the universe?

Knowing the definition of work as used by physicists, how can the work done on an object be equal to zero? a. The force and distance are perpendicular. b. The force is zero. c. The distance is zero. d. all of these e. none of these.

A man weighing 180 lbf pushes a block weighing 100 lbf along a horizontal plane. the dynamic coefficient of friction between the block and plane is 0.2.

The Earth's gravity keeps us from flying out to space. How can you explain that we have a stronger gravitational attraction to the Earth than to the Sun? We are closer to the sun than the Earth. We are closer to the Earth than the sun.

The ends of a magnet where the force is strongest are magnetic A) fields B) poles C) domains D) currents

Which one of the following substances is a liquid fuel used in rocket engines?

V=345m/s, 7210Hz, X=?

As a mercury atom absorbs a photon of energy, an electron in the atom changes from energy level d to energy level e. Determine the energy of the absorbed photon in electronvolts.

During an exothermic reaction, the energy given off comes from atoms being consumed mass being burned into energy the breaking and forming of bonds mass being created

Can electrostatic attract both pull and pull?

Ways that charges can be transferred