P5 Contact and Non-Contact Forces Flashcards
What is vector quantities?
A quantity with magnitude and direction
What are some examples of vectors?
Speed, velocity, displacement, acceleration
What are scalar quantities?
A quantity with only magnitude
What are some examples of magnitude?
Speed, distance, mass, temperature
What is a non-contact force?
Where the objects do not need to be touching for the force to act
What are some examples of non-contact forces?
Magnetic force, gravitational force, electrostatic force
What is a contact force?
When two objects have to be touching for a force to act
What are some examples of contact forces?
Friction, air resistance
What is gravitational force?
The force of attraction between masses
What are two effects of gravitational force?
- It makes all things fall towards the ground
- It gives everything weight
What is weight?
The force acting on an object due to gravity
What does it mean when an object is elastically deformed?
The object can go back to its original shape and length after the force has been removed
What does it mean when an object is inelastically deformed?
The object doesn’t return to its original shape and length after the force has been removed
What is the limit of proportionality?
Where the extension of the spring is no longer proportional to the force
What is a moment?
The turning effect of a force
How do gears transmit rotational effects?
- Gears have teeth which interlock, causing the other to turn in the opposite direction
- They transmit the rotational effect of a force to another gear
- A larger gear causes a bigger moment as the distance is greater but turns slower
What is upthrust?
The resultant force upwards
What does it mean if an object floats?
It is less dense than the liquid because it weighs less than the equivalent volume of fluid so its weight is equal to upthrust
What is Newton’s first law?
If the resultant force on a stationary object is zero, the object will remain stationary. If the resultant force on a moving object is zero, it will just carry on moving at the same velocity
What is Newton’s second law?
The acceleration is directly proportional to force and inversely proportional to the mass of an object
What is Newton’s third law?
When two objects interact, the forces they exert on each other are equal and opposite
What is inertia?
The tendency to continue in the same state of motion
What is thinking distance?
How far the car travels during the driver’s reaction time
What is braking distance?
The distance taken to stop under the braking force
