How can you calculate the number of electrons in an atom

What is the wavelength of a sound wave that has a speed of 250m/s and a frequency of 400hz

15. Describe how the speed of sound would change as it first travels through a Solid: Liquid: Gas: (2pts)

What is the unbalanced force on a car moving with a constant velocity of 25 m/s?

You throw a ball horizontally from the top of a building, with a speed of 3 m/s. In this problem, you can neglect the force of air resistance. After 2 Seconds, what is the balls horizontal velocity? A. Impossible to tellB. Less than 3 m/sC. 3 m/sD.

What can you say about resting membrane potential?

Which is the correct order from the closest to the sun to the farthest away from the sun? A. terrestrial planets, asteroid belt, gas planets, Kuiper belt B. gas planets, asteroid belt, terrestrial planets, Kuiper belt C.

Ethylene (C2H4) reacts with oxygen gas to produce carbon dioxide and water. 45.0 grams of ethylene reacts, how many grams of carbon dioxide gas will be produced?

What causes ice to melt and water to boil

A block of mass 3.5 kg slides down a frictionless inclined plane of length 6.4 m that makes an angle of 30 degrees with the horizontal. if the block is released from rest at the top of the incline, what is its speed at the bottom

What is the wavelength of an earthquake wave if it has a speed of 5 km/s and a frequency of 10 Hz?