Chapter 3 Motion Flashcards
What is the equation for average speed?
Average speed = total distance / total time
What is the difference between speed and velocity?
Speed is a scalar (no direction), velocity is a vector (has direction).
What is the equation for acceleration?
Acceleration (a) = (v - u) / t
Where:
v = final velocity
u = initial velocity
t = time
Name the 5 suvat variables.
s = displacement
u = initial velocity
v = final velocity
a = acceleration
t = time
What are the 5 suvat equations?
- v = u + at
- s = ut + 1/2 at²
- v² = u² + 2as
- s = 1/2 (u + v)t
- s = vt - 1/2 at²
What assumptions are made when using suvat equations?
Constant acceleration and straight-line motion.
How can you find acceleration from a velocity-time graph?
Calculate the gradient (change in velocity / time).
How can you find displacement from a velocity-time graph?
Calculate the area under the graph.
What is free fall?
Motion under gravity only (no air resistance).
What is the approximate acceleration due to gravity on Earth?
g = 9.81 m/s²
What does terminal velocity mean?
The maximum velocity an object reaches when the force of air resistance equals the weight.
What does the gradient of a displacement-time graph represent?
Velocity
What does the gradient of a velocity-time graph represent?
Acceleration
What does the area under a velocity-time graph represent?
Displacement
What causes an object in free fall to reach terminal velocity?
Air resistance increases with speed until it balances weight; net force = 0.
