3rd Law of Motion In this lesson, we will be focusing on Newton’s 3rd Law of Motion. This law is all about pairs of forces called… action and reaction forces Let’s learn a little about these forces…
ESA –stop at summary of 3 laws Newton’s 3 rd law in Space
To recognize 3rd Law of Motion Newton’s 3rd Law of Motion look for pairs of forces… “action” “action” is the force that happens first, “reaction” causing a “reaction” force to happen These equal forces happen in opposite directions.
Newton’s 3 rd Law action-reaction Key Idea is action-reaction The Law says… action for every action (force) equalopposite there is an equal and opposite reaction reaction (force) Let’s look at some examples.
action force When you sit in a chair… (action force) the chair must be pushing back… reaction force (reaction force) these forces are equal in strength and opposite in direction, otherwise you’d land on the floor! Action Reaction At Rest…
When you lean against a wall… action force (action force) the wall must be pushing back equally hard… reaction force (reaction force) otherwise you’d go through the wall! Reaction Action At Rest…
Reaction Action For moving things… action force an action force in one direction creates an equal and opposite reaction force reaction force in the opposite direction
action force an action force in one direction reaction force creates an equal reaction force in the opposite direction Action Reaction
If you haven’t already figured it out… the key idea of Newton’s 3 rd Law is Action – Reaction The Law says… action (force) reaction (force) For every action (force), there is an equal and opposite reaction (force)
Now, it’s your turn to see if you can identify Newton’s 3 rd Law in these demonstrations… Look for equal action – reaction force action – reaction force pairs going in opposite directions