Flashcards in module 5 Deck (14):
What is a vector?
Forece are vector quantity-vector quantities have a magnitude and a direction, lot's of physical quantities are vector quantities: force, velocity, displacment, acceleration, momentum.
What are scalar quantities?
some physical quantities only have magnitude and no direction. These are called scalar quantities: speed, distance, mass, temperature, time etc.
What are vectro qualities?
Usually represented by an arrow-length of arrow shows magnitude and direction of arrow shows direction of quantity.
What are forces?
A push or pull causedby it interacting with something. all forces are contact or non-contact.
Contact: when 2 objects are touching for a force to act.
non-contact: objects that don't touch for a force to act.
What happens when 2 objects interact?
There is a force produced on both objects. An interaction pair is a pair of forces that are equal and opposite and act on 2 interacting objects.
What is gravity?
Attracts all amsses, only noticed with large masses, anything near a planet or star is attracted to it. It makes all things fall to the surface on the ground on a planet, it gives everything weight.
What is mass?
The amount of 'stuff' in an object for any given object, it will have some value anywhere in the universe.
What is weight?
The force acting on an object due to gravity. Close to earth, force caused by gravitational field around earth. Weight of object depends on strength of gravitational field at location of object. Measured in newtons, force acting from single point is centre of mass.
What is gravitational field strength?
Varies in location. Stronger to mass causing field, stronger for larger masses.
How do you calculate weight?
weight=mass*gravitational field strength.
What happens to weight after mass is increased?
If mass increases weight also increases, if double mass, weight doubles-they are directly proportional.
What are fluids and how do their particles act?
Substances that can flow because particles are able to move around. As these particles mover, they collide with surfaces and other particles. Are light but still have mass and exert a force on object they collide with. Pressure is force per unit area, so this means particles exert a pressure.
How does pressure act in fluids?
Means force is exerted (at right angles) to any surface in contact with fluid.