Quiz 1- Force, Work and Energy Study Guide 6th Grade Science – Miss Fox

Motion: an objects change in position relative to a reference point (movement). Inertia: an objects tendency to stay at rest or in motion. Velocity: speed in a particular direction. Acceleration: the rate at which velocity changes over time (speed, direction or both). Mass: is the amount of matter in an object. Weight: force exerted on an object’s mass by gravity.

Speed: Speed is a measure of how far an object travels in a certain period of time.

Force: a push or pull exerted on an object in order to change the motion or direction of an object. Force= mass x acceleration (F=mxa)

Newton (N): units used to measure force.

Spring scale is used to measure force (N - newtons)

Net Force: the combination of all of the forces acting on an object. The net force tells you whether the forces on the object are balanced or unbalanced. Balanced Force: When the forces on an object produce a net force of 0 N, the forces are balanced. Balanced forces will not cause a change in the motion of a moving object or cause a nonmoving object to start moving. Example: a deck of cards.

Unbalanced Force: When the net force of an object is not 0 N, the forces on the are unbalanced and produce a change in motion, speed or direction.

Friction: force that opposes motion between surfaces. There are four types of friction:  Static Friction: when a force is applied to an object but it does not cause it to move (example: pushing on a wall).  Fluid Friction: occurs when a object moves through a fluid, meaning either a liquid or gas (examples: skydiving, swimming).  Sliding Friction: occurs when solid surfaces slide over each other (example: baseball player sliding into first base).  Rolling Friction: occurs when an object rolls over another. Something with wheels or that is circular like a ball (example: riding a motorcycle).

How to decrease friction: add wheels or rollers, lubricate the surface (oil), make the surface smoother, remove weight or pressure. How to increase friction: make the surface rougher or bumpier, add weight or pressure.

Gravity: is a force of attraction between objects due to their masses. Laws of Gravity: 1. The force of gravity between two objects increases as the mass of the objects increase. 2. The force of gravity between two objects decreases as the distance between the objects increases.

Energy: is the capacity to do work. Potential - is stored energy waiting to happen.(for example) a book sitting on a shelf. Kinetic - energy in motion or happening now.(for example) a book falling off a shelf.