Which of the following statements about mass and weight is true? A. mass measures the force of gravity on an object and weight measure the amount of matter an object contains.

B. weight measures the force of gravity on an object and mass measures the amount of matter an object contains.

C. weight and mass both measure the amount of matter an object contains.

D. weight and mass both measure the force of gravity on an object.

An observer that stands still as the electron moves by him, will observe

Considering only the earth's rotation, determine how much later the asteroid would have had to arrive to put the explosion above helsinki at longitude 25˚ e? this would have obliterated the city.

Which statement is true if the refractive index of medium a is greater than that of medium b? a. total internal reflection is possible when light travels from air to medium b to medium a. b. total internal reflection is possible when light travels from medium a to medium b. c. total internal reflection is possible when light travels from medium b to medium a. d. total internal reflection is possible when light travels from air to medium a. e. total internal reflection is possible when light travels from air to medium b.