How many neutrons does element X if it's atomic number is 28 and its mass number is 87

Which waves are longitudinal waves

True or false radiant energy spreads out from its source in all directions

For your selection above, substitute? = 2? T where T is the period of orbit. Kepler found that the cube of orbital radius was proportional to the square of orbital period. Do your findings confirm or contradict Kepler's Rule?

old stars obtain part of their energy by the fusion of three alpha particles to form a 12/6c nucleus, whose mass is 12.0000 u. How much energy is given off in each such reaction?

A crane motor exerts 3,500.0 W to lift a load up 5 floors in 25.0 seconds. The crane did how much J of work.

Two charged parallel plates are 0.25 meters away from each other. The field between the plates is 600. What is the electric potential difference?

A helicopter flying west begins experiencing an acceleration of 3m/s2 east. Will the magnitude of its velocity increase or decrease?

What is a scalar? A. A quantity that does not indicate direction. B. The direction of a vector. C. A magnitude and a direction. D. A measurement of displacement.

How many electrons does nitrogen (N) need to gain to have a stable outer electron shellHow many electrons does nitrogen (N) need to gain to have a stable outer electron shell?

What kind of heat energy does the sun warm you with?