Physics is the study of the forces acting on and between objects. While statics is the study of forces on objects at rest, dynamics concerns the forces (pushes or pulls) imposed on objects when they change their velocity (accelerate). Mass defines an object’s resistance to velocity change, and weight describes an object’s attractive force toward Earth’s center due to the acceleration from Earth’s gravity acting on its mass. Acceleration is the rate at which velocity changes. Dynamic load refers to a force imposed on a system because it is accelerating an object in a given direction.

**Dynamic Load Due to Gravity (Vertical)**

Step 1

Define the application for calculating dynamic load; the weigh scale on an elevator is a good method in which to do so. A 150-pound adult standing on a scale on an elevator at ground level notes their 150-pound reading as they push the button for the 20th floor. The elevator ascends at a rate of 16 feet-per-second.