IB Physics SL - Topic 2: Mechanics

Definition of vector.
They have a magnitude and a direction associated with them
1 of 32
Definition of scalar.
They have a magnitude but no direction.
2 of 32
What does the symbol s mean?
Displacement: the distance moved in a particular direction.
3 of 32
What does the symbol v (sometimes u) mean?
speed: rate of change of distance (speed=distance gone/time taken)
4 of 32
What does the symbol a mean?
Acceleration: the rate of change of velocity (a=change of velocity/time taken)
5 of 32
How do you calculate the relative velocity?
Both object travelling on straight line: subtraction or addition.
6 of 32
Displacement-time graph
Gradient = velocity. Area does not represent anything useful.
7 of 32
Velocity-time graph
Gradient = acceleration. Area under graph is the displacement.
8 of 32
Acceleration-time graph
Gradient: rate of change of acceleration, not useful. area under graph: change in velocity.
9 of 32
How can you practically calculate velocity or acceleration?
*light gates *strobe photography *tick timer
10 of 32
All forces (9)
*Gravitational force *Electrostatic *Magnetic *normal reaction *friction *tension *compression *upthrust *lift
11 of 32
Hooke's law
Up to the elastic limit, the extension, x, of a spring is proportional to the tension force, F. The constant of proportionality is k, the spring constant. Unit: N/m
12 of 32
Free-body diagram
Only one object is chosen. All forces action on it have to be drawn.
13 of 32
Newton's first law
An object continues in uniform motion on a straight line or at rest unless a resultant external force acts.
14 of 32
Define equilibrium.
Resultat force on object equals to zero, it is in translational equilibrium-
15 of 32
Gravitational force
force between objects as a result of their masses (weight).
16 of 32
ELECTROSTATIC FORCE
force between object as a result of their electric charges.
17 of 32
magnetic force
force between magnets or electric currents.
18 of 32
friction force
the force that opposes the relative motion of two surfaces and acts along the surfaces. air resistance and drag are friction forces.
19 of 32
tension force
when a string or spring is streched, it has equal and opposite forces on its ends pulling outwards.
20 of 32
Newton's second law
a resultat force causes an acceleration. (momentum - the resultant force is proportional to the rate of change od momentum)
21 of 32
Newton's third law
when two bodies a and b interact, the force that a exerts on b is equal and opposite to the force that b exerts on a.
22 of 32
Momentum
Linear momentum (p) is defined as the product of mass and velocity, p = m * v. unit: m/s
23 of 32
Impulse
Change of momentum, delta(p) = F delta(t)
24 of 32
Elastic collision
No mechanical energy lost (only real elastic collision is between molecules). Relative velocity of approach always equals the relative velocity of seperation.
25 of 32
totally inelastic collision
objects stick together after collision. relative velocity of separation is zero. total momentum is conserved but majority of the mechanical energy is lost.
26 of 32
inelastic collision
some energy lost, objects don't stick together. momentum is conserved.
27 of 32
Definition of work
W=Force * distance
28 of 32
Relationship between work and energy
the amount of energy transferred is equal to the work done. same unit.
29 of 32
Definition of power
power is the RATE at which energy is transferred. P = W/t (work done/time taken)
30 of 32
Definition of efficiency
Ratio of useful energy to the total energy transferred.
31 of 32
Describe uniform circular motion
an object that is going around a circle at constant speed. direction of object is changing all the time = velocity is constantly changing = object is accelerating
32 of 32

Other cards in this set

Card 2

Front

Definition of scalar.

Back

They have a magnitude but no direction.

Card 3

Front

What does the symbol s mean?

Back

Preview of the front of card 3

Card 4

Front

What does the symbol v (sometimes u) mean?

Back

Preview of the front of card 4

Card 5

Front

What does the symbol a mean?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Forces resources »