mechanics Flashcards
what are the 5 equations of motion
SUVAT
what are the actual values of SUVAT
S = distance travelled
U = initial velocity
V = final velocity
A = constant acceleration
T = time taken
list the four SUVAT equations
v = u+at
s = ut + 1/2at_2
v_2 = u_2 + 2as
s = 1/2(u+v)t
what is speed
the rate of change of distance
what is velocity
the rate of displacement
what is acceleration
how much an object speeds up by every second
what is an objects centre of mass
The average point of all parts of an object weighted according to their
mass. It is the point through which the total mass of the object is said to act.
what is the conservation of energy
In a closed system with no external forces the energy of the
system before an event is equal to the energy of the system after the event. The energy does
not need to be in the same form after the event as it was before the event.
what is the conservation of momentum
In a closed system with no external forces the momentum of
the system before an event is equal to the momentum of the system after the event.
what is drag
The resistance against the motion of an object through a fluid. It is usually proportional
to the speed of the object.
what is elastic collision
When the kinetic energy of a system before an event is equal to the
kinetic energy of the system after the event.
what is impulse
The change of momentum of an object when a force acts on it. Equal to the area
underneath a force-time graph
what is inelastic collision
When the kinetic energy of a system before an event is not equal to the kinetic energy of the system after the event. The kinetic energy has been transferred to other forms.
what is lift
A force acting perpendicular to the flow of air or liquid around an object, typically upwards and against the force of gravity.
what is a moment
The product of a force and the perpendicular distance from the line of action to the pivot about which the force is acting.
newtons first law
An object at a constant velocity will remain at a constant velocity
unless acted on by a resultant force. (If this constant velocity is zero the object is at rest).
newtons third law
Every action has an equal and opposite reaction. If an object A exerts a force on object B, object B will exert a force of equal magnitude but of opposite direction on object A.
