Frictional Force and Terminal Velocity Flashcards
Friction is always there to…
Slow things down.
What happens when an object has no force propelling it along?
It will always slow down and stop because of friction.
Friction always acts in the opposite direction to what?
Movement.
To travel at a steady speed what happens to the driving force?
It needs to balance the frictional forces.
How do you get friction?
Between 2 surfaces in contact.
Object passes through a fluid.
What are most of the resistive forces caused by?
Air resistance and “drag”.
What is the most important factor in reducing drag in fluids?
Is keeping the shape of the object streamlined.
What is the opposite extreme?
Parachuting.
Highest drag you can get.
Drag increases as the…
Speed increases.
Frictional forces from ____ always ____ with ____.
Fluids.
Increase.
Speed.
A car has much more friction to work against when…
It is travelling at a faster speed.
What happens when a car is travelling faster?
Engine works much faster just to maintain steady speed.
When objects fall through fluids what do they reach?
Terminal velocity.
What happens to falling objects when they first set off?
Force of gravity is much more than frictional force slowing them down.
If the force of gravity is much more than the frictional force what happens to the object?
It will accelerate.
As the speed of the object increases…
The friction builds up.
The building up of the friction does what to the object?
Gradually reduces the acceleration.
Eventually what will happen to the object after it reduces in acceleration?
Frictional force is equal to accelerating force.
Won’t accelerate anymore.
When the frictional force is equal to accelerating force the object has reached what?
Its maximum speed.
Terminal velocity.
Fall at steady speed.
The terminal velocity of falling objects depends on what?
Shape.
Area.
What is the accelerating force acting on all falling objects?
Gravity.
Gravity would make objects fall at the same time if it wasn’t for?
Air resistance.
What does air resistance cause?
Things to fall at different speeds.
What is the terminal velocity of any object determined by?
Its drag in comparison to its weight.
What does frictional force depend on?
Shape and area.
