C5 - forces moments and pressure Flashcards
what 4 forces act on an airoplane
weight
thrust
lift
drag
what is the centre of gravity
where the weight of an object apears to act on
how can we find the centre of gravity
suspend object freely from 3 point and dew where straight line hanging next to it touches, where 3 lines overlap is the centre of gravity
what is the moment of a force
force x perpedicular distance of the pivot form the line of action of the force
what equation cabe used to find moment of force acting at angle to the pivot
F x dsin()
how can an object be defined as in in equilibrium
the clockwise moments equal the anticlockwise moments about the same point
what is a couple
a pair of equal forces acting on an object causing it to turn but not accelerate
what is equation for torque
one of the forces x perpendicular distance between these forces
what conditions must be meant for object to be equilibriam
resultant force acting in object = 0
resultant force = 0
what does density tell us
how concentrated the matter is
what is equation for decity
mass/volume KGM-3
what does pressure tell you
how the force is shared out over the area
what is equation for pressure
normal force/cross sectional area 1NM-2
