What kind of valves are used on water mains?

An apple falls out of a tree from a height of 2.3m. what is the impact speed of the apple

What is the difference between a mechanical wave and an electromagnetic wave? A mechanical wave travels through empty space, while an electromagnetic wave travels through matter.

I will fan and give 2 medals! Why is it necessary to be able to replicate the results of a scientific experiment? (this is short answer)

When you step on the accelerator to increase the speed of your car, the force that accelerates the car is: A. the force of your foot on the accelerator B. the force of friction of the road on the tires C. the force of the engine on the drive shaft D.

A source emits monochromatic light of wavelength 495 nm in air. when the light passes through a liquid, its wavelength reduces to 434 nm what is the liquid's index of refraction? a. 1.14 b. 1.49 c. 2.03 d. 1.26 e. 1.33

In the nucleus of all atoms are sub-atomic particles called protons and neutrons. all protons have a positive charge.

In a polar covalent bond

Lindsay is late to class and is running down the hallway at a speed of 2 m/s the length of the hallway is 150 meters. How long will it take her to run down the hallway?

Which of the following is evidence that groundwater causes erosion and deposition?

Changing the direction of current will or will not affect the strength of an electromagnet