1 - Forces & Motion Flashcards
What is power?
The rate at which work is done per second
What is meant by “work done” ?
- Energy transferred
- force causing an object to move
What is the gravitational field strength on earth?
10N/Kg
What is weight measured in?
Newtons
What is weight equal to?
Force
What is grams to kilograms?
Divide by 1000
What is cm to metres
Divide by 100
What does the area under a velocity time graph show?
Distance travelled
What are scalars?
Quantities that have only a magnitude
What is a vector?
Quantities with both magnitude and direction
What are examples of scalars?
Speed, distance, mass
What are examples of vectors?
Velocity, acceleration, weight
What is friction?
The force which opposes the motion of an object
Stopping distance =
Thinking distance + braking distance
What factors effect stopping distance?
Car speed, car mass, road conditions
What two forces do falling objects experience?
Weight and air resistance
What does hooke’s law state?
The extension of an elastic object is directionally proportional to the force applied, up to the limit of proportionality
When does elastic deformation occur ?
When objects return to their original shape when the stretching force is removed
When does inelastic deformation occur?
When objects remain stretched when the stretching force is removed
What is terminal velocity?
When there is no resultant force and the object reaches a steady speed.
Describe the stages of terminal velocity
- weight acts downwards
- drag acts upwards
- object accelerates + drag increases
- eventually drag = weight
- object travels at a constant speed
