P8 - Forces In Balance 2️⃣ Flashcards
What is a scalar quantity?
A scalar quantity only has magnitude (size)
What is a vector quantity?
A vector quantity has magnitude (size) and direciton
What is displacement?
Distance in a given direction
What is Newtons 3rd Law?
When an objects interact, they always exert equal and opposite forces on eachother
What is a contact force?
A force where the objects are physically touching
What is a non-contact force?
A force where the objects are physically separated
What is Newtons 1st Law?
An object will remain at a constant velocity unless a resultant force acts upon it
What is a resultant force?
A single force equivilent to all the forces acting on an object
Give 5 examples of a contact force
- fricton
- air resistance (drag)
- tension
- normal contact forces
- upthrust
Give 3 examples of a non-contact force
- gravity
- magnetic force
- electrostatic
The weight of an objects depends on what?
The gravitational field strength at the point where that object is
What is a moment?
A moment is the turning effect of a force
What is the pivot?
The centre of rotation
What is another name for a pivot?
A fulcrum
What is the principle of moments?
If an object is at equilibrim, the sum of all the clockwise moments about any point = the sum of all the anticlockwise moments about that point
