Flashcards on 9 Space Travel, created by Yeung Kam Fan on 09/04/2016.
|
Created by Yeung Kam Fan
over 10 years ago
|
|
Close
|
|
Created by Yeung Kam Fan
over 10 years ago
|
|
9 . 1
When we apply a force on an object , what will happens to the object ?
There are two kinds of forces , states them.
Gives some example of the two kinds of force .
In the laboratory , How can we
measure the forces ?
9 . 2
What is friction ?
What is air resistance ?
Briefly explain the heating effect of friction .
Why we need to reduce the friction ?
How can we reduce the friction ?
9 . 3
What is the force of gravity ?
What is mass ?
What is weight ?
