Question

1. p. 329 what is the scientific unit used to measure force? 4. p. 330 what is a contact force? 5. p. 330 what does it mean when you have an applied force? and give one example.

Explanation:

1. In physics, the scientific unit for force is the Newton (N), named after Sir Isaac Newton. It is defined based on Newton's second - law of motion, $F = ma$ (force equals mass times acceleration).
2. A contact force is a force that acts between two objects in physical contact with each other. For example, when you push a book across a table, the force exerted by your hand on the book is a contact force.
3. Having an applied force means an external force is acting on an object. For example, when you kick a soccer ball, the force from your foot on the ball is an applied force.

Answer:

1. The scientific unit used to measure force is the Newton (N).
2. A contact force is a force between two in - contact objects. Example: pushing a book on a table.
3. It means an external force acts on an object. Example: kicking a soccer ball.