forces and motion Flashcards
what is meant by equilibrium?
forces being balanced
resultant force =0
What is the opposite force to weight?
Air resistance or normal reaction
What is the opposite force to weight?
Air resistance or normal reaction
What is the opposing force to driving?
Frictional force
What force acts on a light inextensible string?
Tension
What force acts on a tow bar when accelerating?
Tension
What forces act on a tow bar when decelerating (braking)?
Thrust because its under compression
Friction equation at limiting equilibrium?
F= coefficient of friction (u) x normal reaction (R)
Friction when stationery
F <_ uR
Friction when moving
Fmax= uR
Factors effecting friction
Materials
Weight
( The reaction between object and surface )
how are pulleys forces treated?
in the direction of motion not as horizontal and vertical components
what does inextensible mean?
it wont stretch therefore acceleration remains the same across the objects
what does rod imply?
that it doesn’t bend and has no thickness
what would occur at a rope connecting vehicles when decelerating (braking)?
the rope will slack
when a rope slacks what is the tension
T= 0
what forces does a vehicle experience
( ->) D - F or B (when braking/decelerating)
is tension experienced by a connected vehicle the same as friction?
no friction and tension are two different forces
what do you do when you are not told what the direction of motion is?
compare the weights
or
assume direction and check for sign of acceleration
