P8 - Forces in Balance Flashcards
What is a vector quantity?
-Physical quantities that have size (magnitude) and direction.
What is a scalar quantity?
-Physical quantities (measurements) that have a size (magnitude) but no direction
What is the difference between distance and displacement?
-Distance includes a change in direction whereas displacement does not have a change in direction
Is speed a scalar or vector quantity?
-Scalar
What are three examples of non-contact forces?
- Gravity
- Magnetic
- Nuclear
What are three examples of contact forces?
- Friction
- Air resistance
- Upthrust
What do need to use to describe a force?
- Name
- Cause
- Direction
What can force change?
- Shape
- Motion (speed/direction)
- State of rest
What do you measure forces in?
-Newtons
What is Newton’s third law?
-Every force has an equal and opposite force.
What is resultant force?
-A resultant force is the single force that has the same effect as all the forces acting on an object.
If a resultant force is zero, what does that mean?
-The forces are balanced
What is Newton’s first law?
-Any object either remains at rest or continues to move a constant velocity unless acted on by an external force
What is the first scenario for Newton’s first law?
-If it’s not moving, it will not start to move unless there is a resultant force
What is the second scenario for Newton’s first law?
-If it is moving, its velocity (speed and direction) will not change unless there is a resultant force
What is the moment equation?
-Moment = force * distance
What can give you a bigger turning force?
-Bigger difference in gears
What does a low gear give you?
- Low speed
- Higher turning effects
What does a high gear get you?
- High speed
- Low turning effects
What is the principle of moment?
-That for something to be balanced the sum of the clockwise and anticlockwise moments must be zero.
