Mass and weight are often used interchangeably, but they are actually two different concepts. Mass refers to the amount of matter in an object, while weight is the measure of the force of gravity acting on an object. In other words, mass is constant and does not change with location, while weight can vary depending on the strength of gravity.
Mass is typically measured in units of kilograms (kg) using a balance or scale. The standard unit of mass in the International System of Units (SI) is the kilogram, which is defined as the amount of matter in an object that has a specific relationship to the mass of a platinum-iridium cylinder kept at the International Bureau of Weights and Measures in France.
Acceleration is the rate of change of an object's velocity. It is a vector quantity, meaning it has both magnitude (speed) and direction. An object can accelerate by changing its speed, direction, or both. The SI unit for acceleration is meters per second squared (m/s²).
According to Newton's Second Law of Motion, the acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to its mass. In simpler terms, the more mass an object has, the more force is needed to accelerate it at a given rate. This is why heavier objects require more force to move or change direction than lighter objects.
Acceleration can be calculated using the equation a = (vf - vi)/t, where a is acceleration, vf is final velocity, vi is initial velocity, and t is time. This is also known as the average acceleration formula. In cases where acceleration is constant, it can also be calculated using the formula a = F/m, where F is the net force acting on the object and m is the mass of the object.