What do astronomers call a system that is composed of more than two stars

Which statement is true about two isotopes of the same element? A. They have the same mass number. B. They have different numbers of protons. C. They have different locations on the periodic table. D. They have different numbers of neutrons.

What causes an object to move, change direction or change speed? a balanced force an unbalanced force any force exerted on it

What is the force between two objects with the masses of 150 and 200 kg and separated by 100 m

Lithium is a metal with an oxidation number of 1 + and oxygen is a nonmetal with an oxidation number of 2-. Which chemical formula represents the compound formed by these two elements?

Which is likely to produce the brightest spectra? A. Holographic gratings B. Reflection gratings on plastic C. Transmission gratings on glass D. Replica transmission gratings on plastic

the half-life of carbon - 14 is 5730 years. What fraction of carbon-14 would remain after 11,460 years?

An object with a mass of 10.9 kg experiences a force of 18.53 N. What is the acceleration of the object? A. 2.2 m/s2 B. 1.7 m/s2 C. 16.83 m/s2 D. 1.3 m/s2

A proton, starting from rest, accelerates through a potential difference of 1.0 kV and then moves into a magnetic field of 0.040 T at a right angle to the field. What is the radius of the proton's resulting orbit

Which of the following terms are needed to completely describe speed? Check all that apply. A. Units B. Direction C. Number D. Mass

Drivers are able to see objects ahead of them because light travels through windshields.