Answer:
The extension of the spring is 0.392 m.
Explanation:
Given;
spring constant, k = 50 N/m
mass attached to the spring, m = 2.0 kg
let the extension of the spring = x
The extension of the spring is calculated by applying Hook's law;
F = kx
mg = kx
Therefore, the extension of the spring is 0.392 m.
Answer: 1687.5 N
Explanation:
From the second law of motion given by Newton, Force is the rate change of momentum.
Mass of the baseball, m = 0.15 kg
Initial velocity, (negative because direction of initial velocity is opposite to the final velocity)
Final velocity,
The duration of collision,
Force,
Hence, the value of force is 1687.5 N.
Answer: Equal number of protons and electrons. Example: an atom of oxygen atom has 8 electrons and 8 protons and is neutral.
Explanation:
An atom that has no charge is a neutral atom. It contains electrons equal to protons. For example: A neutral atom of oxygen has 8 protons and 8 electrons.
An atom which has charge is said be ionized. It is either positively charged or negatively charged. It is positively charge when the number of electrons is less than the number of protons. For example: contains 10 electrons and 11 protons.
And when the number of electrons is greater than the number of protons, the atom is negatively charged. For example, has 17 protons and 18 electrons. It readily accepts an electron to complete its octet.