Physics Flashcards
What are Newton’s laws?
Newton’s first law - inertia.
Newton’s second law - acceleration
Newton’s third law - action-reaction pairs.
What are some types of forces?
Gravitational pull (instead of gravity)
Applied force
Normal force (from the earth)
Friction
Drag (Air resistance)
Forward forces
What unit is used to measure force?
Newtons (N)
What is the formula for average acceleration?
Avg. Acceleration = change in velocity/time
= (final velocity (vf) - initial velocity (vi))/time
OR (vf - vi)/time
What formula is used for Newton’s second law?
F = ma. Force = Mass x Acceleration.
This is directly proportional i.e., Increased force, increased mass, etc.
Describe Newton’s first law.
Newton’s first law (law of inertia) states that objects remain stationary or at a constant speed/direction unless acted upon by an unbalanced force (net force).
Describe Newton’s second law.
Newton’s second law (law of acceleration) states that if a net force is applied onto an object it will accelerate or decelerate (speed up/slow down) - positive/negative acceleration. Acceleration is any change in velocity which can be either speed or direction. (measured in m/s/s)
Describe Newton’s third law.
Newton’s third law (action-reaction pairs) states that for every force, there is another force equal in magnitude and opposite opposite in direction.
Define net force.
The sum of all forces acting upon an object.
What are five car safety features?
Crumple zone
Airbags
Head rests
ABS braking system
Seat belts.
What is the speed equation?
S = d/t. –> units are usually m/s or km/h.
How can km/h be converted to m/s and vice versa?
m/s = km/h divided by 3.6
km/h = m/s x 3.6.
What is instantaneous speed?
The speed at any given point throughout a journey.
What is the average speed?
The speed over a period of time rather than just one instant.
What is the relationship between distance-time graphs and speed-time graphs?
The gradient of a distance-time graph is equal to the speed of the travelling object.
