What is the weight of a 200 kg mass?

Describe the path of a ray that approaches a mirror parallel to the principal axis.

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2