Answer: A
Causing air molecules to vibrate
Explanation:
Sound is made by vibrations. And it is an energy. When any object vibrates, it causes movement in the air particles. These particles bump into the particles close to them, which makes them vibrate too causing them to bump into more air particles. This movement, called sound waves, keeps going until they run out of energy.
Answer: The horizontal velocity of a projectile is constant (a never changing in value. The vertical velocity of a projectile changes by 9.8 m/s each second.
Explanation: I hope that helped!
Aluminum foil (I think, it may not be right)
Answer: There are number of electrons.
Explanation:
We are given 50 Coulombs of charge and we need to find the number of electrons that can hold this much amount of charge. So, to calculate that we will use the equation:
where,
n = number of electrons
Charge of one electron =
Q = Total charge = 50 C.
Putting values in above equation, we get:
Hence, there are number of electrons.
