Motion Chapter 2

Forces FORCE - push or pull applied to an object; can cause motion to change NET FORCE – combined force of two or more forces BALANCED FORCES –forces equal in size and opposite in direction

Inertia INERTIA tendency of an object to resist changes in motion; larger mass = larger inertia Object in motion stays in motion Object at rest stays at rest

Newton’s 1st Law of Motion NEWTON’S FIRST LAW OF MOTION An object moving at a constant velocity keeps the same velocity unless an unbalanced force acts on it. LAW OF INERTIA

Wear Your Seat Belt You are twice as likely to die in a crash if you don't wear a seatbelt Drivers and passengers aged 17-34 have the lowest seatbelt-wearing rates combined with the highest accident rate People are less likely to use seatbelts on short or familiar journeys https://www.youtube.com/watch?v=d7iYZPp2zYY

Distance vs. Displacement DISTANCE – actual length an object moved DISPLACEMENT – length an object moved from it’s starting position Both are usually measured in meters (m) or kilometers (km)

Speed vs. Velocity SPEED – TOTAL distance an object travels per unit of time (rate of travel) VELOCITY – rate of travel in a specific DIRECTION Both are usually measured in meters per second (m/s) or kilometers per hour (km/h)

Average vs. Instantaneous Speed AVERAGE SPEED – total distance traveled divided by total time traveled (speed over the whole trip) INSTANTANEOUS SPEED – speed at a given point in time Both are usually measured in meters per second (m/s) or kilometers per hour (km/h)

Calculating Speed S = d t Formula: Steps to Solve Problems: S = speed (m/s) d = distance (m) t = time (s) S = d t List the formula being used List the variables in the formula Record the values for the variables you have been given Substitute the values in the formula Record the final answer with units