What is internal energy?
when an object has speed
the movement of particles
the random movement of molecules and the attractive forces between them when they're together
What is chemical energy
energy can be released when the arrangement of atoms is altered
energy can be released by reorganising the protons and neutrons in an atoms nucleus
where an object is at a high level in the earth's gravitational field
What is energy?
the ability to do work
the work done by a force
work done per unit time
Which of these are examples of potential energy?
chemical
electrical potential
electromagnetic
gravitational potential
nuclear
internal
sound
kinetic
What is a kinetic type of energy?
where movement is taking place
regions where electric, magnetic, gravitational or nuclear forces exist
The conservation of energy is: In a closed system, energy may be converted form one form into another but never created or destroyed
What is the equation for kinetic energy?
1/2mv^2
mgh
mgv
1/2mv
What is energy measured in?
Joules
Newtons/metre
Joule metre/second
What is work done?
focre / distance
force x distance moved in the direction of force
force x energy
energy x distance
force / time
Work done is the energy transferred when a force is mode through a distance
What is power and what is it measured in?
work done/ time taken
watts
joules
work done x time
One watt is the power generated when one joule of energy is transferred to an object.
What is weight?
The gravitational force on an object
mass x gravity
the mass of an object
What is terminal velocity?
the velocity at which an objects drag equals its acceleration force
for free fall - when weight = drag
the fastest possible velocity
when you're accelerating
At terminal velocity:
kinetic energy is constant
the GPE is transferred to the surrounding air as heat
The loss in KE is the work done by the drag force
The larger the surface area of an object, the smaller the terminal velocity because there is more drag so you don't accelerate as much before drag = weight.
The larger the mass, the smaller the terminal velocity
What is stopping distance?
The time taken for a car to stop
The total instance a car travels from the moment the driver sees a hazard
The time taken from the moment the driver has pressed the break
Factors that increase thinking distance:
under the influence of alcohol or other drugs
tiredness
distractions
high speed
weather
intelligence
The work done to stop an object will be equal to the change in kinetic energy of the object
Factors that increase breaking distance
mass of vehicle
road conditions
car conditions
driver distractions
alcohol/drugs
If speed of a car doubles:
kinetic energy quadruples
work done quadruples
breaking distance quadruples
An air bag works by: deflated nylon bag attached to a crash sensor which measures acceleration and detects when you are breaking very sharply. It releases two chemicals which react rapidly and produce nitrogen gas which inflates the airbag.
What is trilateration?
using four satellites together to determine the position of something
The distance from a satellite to the earth
The orbit of a satellite
