Two objects needed
A force comes from an interaction.
Pushing a table
You push a table with your hand.
How many objects are involved in this push?
What this lesson covers
The idea
A force on an object results from its interaction with another object, so at least two objects must interact for a force to come into play.
Pushing a table
You push a table with your hand.
How many objects are involved in this push?
- Two
- One
- Three
Pick a pair
Choose a pair of objects. Press Push, then Stop pushing.
Always a pair
When you push the table, your hand is one object applying a force on another object, the table. A force needs two objects that interact.
A force on an object results from its interaction with another object. So at least two objects must interact for a force to come into play.
- Action | Objects that interact
- Pushing a table | Hand and table
- Kicking a football | Foot and football
- Pulling a drawer | Hand and drawer
Notes
A force on an object comes from its interaction with another object. At least two objects must interact.
Check yourself
At least how many objects must interact for a force to come into play?
Answer: 2
At least two objects must interact.
Your hand pushes a table. Which two objects interact?
A force on an object results from …
A foot kicks a football. Which two objects interact?
- The hand and the table — correct. Yes!
- Only the table. The hand is the other object in the interaction.
- Only the hand. The table is the other object in the interaction.
- the object being alone. A force needs a second object to interact with.
- its interaction with another object — correct. Yes!
- the colour of the object. Colour does not make a force. An interaction does.
- The football and the sky. The foot is the object that interacts with the football.
- Only the football. A force needs two objects. The foot is the second.
- The foot and the football — correct. Yes!