Physics 2 Flashcards
(22 cards)
Contact forces
Include friction, drag, upthrust and reaction
Non-contact forces
include weight, magnetic force, Electro forces and gravitational forces
representing forces
The size of the arrow represents the size of the force
Friction
Friction is the force that opposes movement caused by contact between two surfaces
factors affecting forces
Mass of the object, shape of the object and the surface that it is on can affect the friction forces
Streamlining
Streamlining reduces friction and drag forces
Resultant force
The result of force is a single force that has the same effect as all the forces acting on the object.
Arrows in the same direction or added and hours and opposite direction of subtracted .
zero resultant force
A resultant force or zero can mean the object is stationary or moving at a constant speed
Not zero resultant force
resultant force that is not zero can mean the object is a accelerating or decelerating
hooke’s Law
Hooke’s law states that the extension of a spring is proportional to the force applied less elastic limit has been reached
Spring constant
The spring constant (k) describes the stretchiness of the springs, the higher the number the stiffer the spring
work done
Work done = distance X force
work is done on an elastic object when it changes and it stores elastic potential energy
Weight
weight is a force and is measured in Newton’s and mass is measured in KG.
Day and night
A day and night is 24 hours long it is the amount of time for the Earth to rotate one fully on its axis
year
A year 365.24 days long, it is the amount of time for the Earth to complete one full orbit around the Sun.
seasons
The summer is hotter because the sun rays are spread over a smaller area when the Earth is tilted towards the sun
Luminous object
The Sun and stars are the only luminous object, everything else reflects light
Phases of the moon
The moon appears to change shape as the amount of the moon visible from the Earth changes
Solar eclipse
A solar eclipse is when the sunlight is blocked by the moon
Lunar eclipse
is when the moon cannot be seen because it is in the Earth shadow
Objects
objects in our universe in size order is comet, moon, plant, star, solar system, galaxy and universe
The planets
The planets in order are mercury, Venus, earth, Mars, Jupiter, Saturn, Uranus and Neptune
The further from the Sun the planet is the cold. The planet surface is, except from Venus that is the hottest planet.
