Which of the following statements is not true about speed?
a. speed has no direction.
b. speed is a vector quantity.
c. speed and position are separate variables.
d. speed is measured relative to another object.

An incident ray through the focal point of a spherical mirror will: reflect through the center of curvature. reflect back through the focal point. reflect parallel to the principle axis. reflect the same direction as the incident ray.

Which object is most likely represented by a dot?

Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.