C4 Forces In Action Flashcards
What does a resultant/ net force on an object do
The object will accelerate in the direction the force is being applied
Standard equation for force
F = ma
What is weight
The gravitational force acting on an object
Acceleration of free fall on the moon?
1.6ms^-2
What is the centre of mass
A point where any externally applied force only produces straight line motion and no rotation
Friction definition
The force that arises when two surfaces rub against each other
Drag def
The resistive force on an object travelling through a fluid
Tension def
The force within a stretched cable or rope
Upthrust
An upwards buoyancy force acting on an object when it is in a fluid
Normal contact force
A force arising when one object rests against anither object
What does an object moving throigh a fluid always experience naturally
A drag force
Most prominent factors that effect drag force on an object
The objects speed and cross-sectional area
What is drag force proportional to?
Drag force is directly proportional to velocity ^2
Moment of a force definition
The moment of a force is the turning affect of a force about an axis or a point
What distance must be used in moment calculations
Perpendicular distance
Principal of moments
For a body to be in rotational equilibrium, the sum of the anticlockwise moments about any point is equal to the sum of the clockwise moments about that same point
Torque of a couple equation
Torque = one of the forces*perpendicular seperation between the forces
Density definitin
Mass per unit volume
Pressure definition
The normal force excerted per unit area
What are fluids
Substances that can flow
Pressure caused by a column of liquid
Pressure = height of a columndensity of a liquidacceleration of free fall
Unique feature of fluid pressure
The pressure in a fluid at any particular depth is the same in all directions
What is archimedies principle
The upthrust excerted on a fluid, whether partially or fully submerged, is equal to the weight of the fluid that the body displaces
