Mechanics
IB Physics: Mechanics
IB Physics: Mechanics
Fichier Détails
| Cartes-fiches | 12 |
|---|---|
| Langue | English |
| Catégorie | Physique |
| Niveau | Autres |
| Crée / Actualisé | 18.04.2013 / 01.08.2017 |
| Lien de web |
https://card2brain.ch/box/mechanics
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Define Average Velocity.
The total displacement of the object in the total time:
Velocity (Vav) = total displacement (s) / total time (t)
Define Instantaneous Velocity.
The velocity at any one instant:
v = Δs / Δt
Where Δt is tending towards zero
v = ds / dt
velocity is the derivative of displacement with regards to time
What does the slope on a displacement-time graph represent?
velocity
What does the slope on a velocity-time graph represent?
acceleration
What does the area under a velocity-time graph represent?
displacement
What does the area under an acceleration-time graph represent?
velocity
How many equations of uniformly accelerated motion are there?
What is the first suvat equation, which is concerned with finding acceleration or velocity?
a = change of velocity / time taken
a = final velocity (v) - initial velocity (u) / time (t)
therefore: v = u + at
What is the second suvat equation, which is concerned with finding displacement without use of acceleration?
Since: average velocity = initial velocity (u) + final velcoity (v) / 2
and: average velocity = displacement (s) / time (t)
s / t = u +v / 2
Therefore: s = 1/2 (u + v) t
What is the third suvat equation, which is concerned with finding displacement without the use of final velocity?
Since: final velocity = initial velocity + acceleration * time
v = u + at
Hence: s = 1/2 (u + u + at) t
and: s = ut + 1/2 at2
What is the fourth suvat equation, which is concerned with finding final velocity without the use of time?
Eliminate t from suvat equation 3 by substituting:
t = (v - u) / a
which can be derived from suvat equation 1 to make:
v2 = u2 + 2as
When are the suvat equations useful?
When three or four of s, u, v, a or t are known and the others need to be found.
