What is the purpose of the mucus in the digestive system?

What is the name of the process by which a substance changes directly from a solid to a gas without passing through the liquid phase?

What is the SI unit of power?

Which of Newton's laws states that an object at rest will stay at rest, and an object in motion will stay in motion with the same speed and in the same direction unless acted upon by a net external force?

What is the phenomenon where a vibrating system or external force causes another system to oscillate with greater amplitude at a specific frequency?

Which type of cloud is thin and wispy, found at high altitudes and composed of ice crystals?

Which of the following is an example of a non-contact force?

According to the law of conservation of energy, what happens to the total energy in a closed system?

Which of the following is an example of a non-conservative force in physics?

What force opposes the relative motion or tendency of such motion of two surfaces in contact?