Machines Flashcards

Vocabulary flashcards for the Machines event in Science Olympiad, covering key terms and concepts from the lecture notes.

Mechanical Advantage

A factor by which a machine multiplies force; the ratio of output force to input force. A greater distance of application of force means less force required.

Ideal Mechanical Advantage (IMA)

The number of times a machine would multiply an effort force if there were no friction or wear.

Actual Mechanical Advantage (AMA)

Experimentally determined mechanical advantage which takes friction and wear of the machine into account.

Efficiency

The effect of friction and wear of the device on the output work, also the ratio of output work to input work.

Friction

Any force acting in the opposite direction of the net force on an object.

Torque

The rotation equivalent of force; force times the perpendicular distance between where the force is applied and the fulcrum.

Power

How fast energy is being transferred or work is being done from one object to another.

Kinematics

Describes the motion of a body in space.

Linear Velocity

The rate at which an object is traveling per time.

Acceleration

The rate at which an object's velocity is changing per time.

Inertia

An object's resistance to change in velocity.

Momentum

The product of an object's mass and velocity.

Impulse

The product of an exerted force and time of an object; also defined as the change in momentum of an object.

Simple Machine

A mechanical device for applying force.

Compound Machine

Made of two or more simple machines.

Pulley

A wheel on an axle that is designed to support movement and change of direction of a cable or belt along its circumference.

Inclined Plane

A flat surface (a plane) that is on an angle (an incline).

Wheel and Axle

Consists of two parts, a wheel and an axle, in which both parts rotate with each other as a force is transferred from one to another.

Lever

A rigid bar resting on a pivot point, known as the fulcrum.

Wedge

A triangularly shaped compound inclined plane.

Screw

Essentially an inclined plane wrapped around a central axis.

Gear

A rotating machine part with teeth.

Differential Pulley

Made of two pulleys and one string, with a high mechanical advantage and relatively simple design.

Newton’s First Law of Motion

An object at rest stays at rest, and an object in motion stays in motion unless acted upon by a net external force. An object tends to keep going in it’s certain direction unless acted on by another force. Defines inertia.

Newton’s second law of motion

Defines acceleration, the change in velocity of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

Newton’s third law of motion

For any force applied, there is an equal and opposite force, such as the normal force.