Answer:
a. Doppler and transit observations.
Explanation:
By means of the dopler effect, the radial velocity of an extrasolar planet can be measured, this is achieved by observing Doppler shifts in the spectrum of the star around which the planet orbits. This measure, combined with the transit observations, makes possible determine the density of the planet.
Answer:
A force of μk⋅60N is needed to keep a 60-newton rubber block moving across level, dry asphalt in a straight line at a constant speed.
Explanation:
Answer:
Anything in an experiment that remains unchanged.
Explanation:
An example could be the temperature of the laboratory room. If there is something that has an effect on an experiment that is not variable, it is a constant. Another constant could be, say, if you were doing calculations with the same amount and kind of fluid throughout the experiment, then that fluid would also be a constant.