Forces Flashcards
Speed
Speed = distance / time
Speed is the distance a object travels at a given time
Velocity
Velocity is a vector
+10m/s (velocity of 10m/s to the right)
-10m/s (velocity of 10m/s to the left)
Acceleration
Acceleration = change in velocity/ time taken
Acceleration of free fall (g)
9.8m/s^2
Represented by the letter (g)
Measuring (g)
g = 2(height)/time^2
Forces (vector)
Measured in newtons To measure small forces, we can use a spring balance. Upthrust- upward force from a liquid Weight - gravitational pull Tension - stretched material Friction - Thrust - forward force from an aircraft Air resistance- a type of friction
Terminal velocity
terminal velocity, steady speed achieved by an object freely falling through a gas or liquid.
Newton’s first law
If no external forces act on a object,
If stationary the object remains stationary
If moving, moves in a constant speed
Inertia
When a object remains at rest or in uniform motion in the same straight line unless acted upon by some external force
Resultant force
Mass x acceleration
Dynamic friction
It is the friction, experienced by a body, when in motion.
Earth’s gravitational field
10N/kg
How to work out weight
W = mass x 10N/kg
The moon’s gravitational field strength is weaker than earth’s
So your weight would be less on earth, as compared to the moon.
Newton’s third law
For every action there is a equal and opposite reaction
Vectors
Quantities that have a direction and magnitude
- momentum
- displacement
- force
- acceleration
