Mechanics Flashcards
What effect can a force have on an object? (3 marks)
A force is an interaction between 2 objects that can cause a change in speed, direction or shape
what is a field
a field is a reigion where an object in that feild will feel a force IF that field affects it
4 fundemental forces?
Gravity (b’w object+mass)
Weak Force(governs particle decay)
Electromagnetism(b’w electricalling charged particles)
Strong Force(binds quarks together)
average speed
s
Equation:
Total distance/total time
Units
m/s, cm/s, km/s
acceleration
a
Equation:
Final velocity/inital velocity
Units
m/s2
weight
W
Equation:
mass x gravity
Units
N
Force
F
Equation:
Mass x Acceleration
N
Hookes Law
Equation:
spring constant x extension
Units
N
Moment / Torque
M, T
Equation:
force x distance
Units Nm
Pressure
P, p
Equation:
Force/ Area
Units
N/m2, Pa
Pressure in fluid
Equation:
Density x gravity x height
(Dgh)
Units
Pa
If forces on a car are balanced is the car moving?
Yes
U dont need unbalanced for movement u need unbalanced for acceleration or change in movement
if a plank of wood is hanging from the roof by two rodes, what is holding it up?
Tension
Why cant we accelerate forever?
when an objects moving theres always a constant force acting on it
The size of the drag or air resistance depends on the objects speed as the speed increases the drag increases
faster=more drag=more force= movement slows
as force decrease acceleration decrease
how does mass and S.A affect air resistance
Mass- not at all
S.A- more S.A more resistance
