Forces and Acceleration Flashcards
What is the difference between speed and velocity?
Velocity has direction specified.
What is acceleration?
How quickly the velocity is changing.
What are the two ways that acceleration can change?
- Change in speed
2. Change in direction
What is the formula for acceleration?
v-u
t
What is the gradient of a distance-time graph?
Speed
What is the gradient of a velocity-time graph?
Acceleration
How do you find the velocity on a velocity-time graph?
The value of the velocity axis
How do you find the distance travelled on a velocity-time graph?
Area under the graph
What are the two effects of gravity?
- Makes everything accelerate towards the ground
2. Gives everything a weight
What is weight?
The pull of the gravitational force.
What is weight measured in?
Newtons, N.
What is the formula for mass, weight and gravity?
W = m x g N = kg x N/kg
What is resultant force?
The overall force on a point or object.
How is resultant force found?
Adding or subtracting parallel forces acting on the same line.
What does a resultant force cause?
A change in the object’s velocity.
If the resultant force on a stationary object is zero…
… the object will remain stationary.
If there is no resultant force on a moving object…
… it’ll just carry on moving at the same velocity.
If there is a non-zero resultant force…
… then the object will accelerate in the direction of the force.
What is terminal velocity?
The maximum speed that an object can fall through a fluid.
How is terminal velocity reached?
- Speed increases, friction increases
- Frictional force balances accelerating force
- Object stops accelerating
What does frictional force depend on?
Shape and area.
What other factor is there in terms of terminal velocity?
Air resistance.
