science physics

what is newtons 1st law

an object will remain at rest or in uniform motion (constant speed) unless acted apon by an unbalanced force. When asnwering newtons first law state the law in the answer.

what is inertia

the property of objects to resist a change in their motion

relate newtons first law to real world examples to explain and predict motion

a soccer ball on the grass will not move until a player (the force) kicks it. You can predict that the ball will remain exactily where it is unless interacted with.

what does zero net force result in

it results in either an object remaining at rest or continunig to move at a constant velocity

what is newtons 2nd law

the acceleration of an object is inversely proportenal to the mass, and directly proportenal to the force applied, so the more hevier objects are harder to push and bigger pushes makes things speed up faster.

what is newtons 2nd law eqation

F=ma

force (N) = mass (kg) x acceleration (m/s)

newtons 2nd law in a real world example to explain and predict motion

an empty cart, a light push makes the cart exelerate quickly. a full cart with the same push results in much less axereration, you must provide a much greater force to make it accelerate the same way.

vector 1

1

vector 2

2

vector 3

3

vector 4

4

what is newtons 3rd law

for every action (force) there is an equal and opposite reaction (force). it describes how objects push off other objects in order to move

newtons 3rd law in real life

an example is a rocket. for the rocket to be able to move upwards it has to push gas downwards in the opposite direction and then it is able to move.

newtons 3rd law in a real world example to explain and predict motion

an example is walking. the action is pushing your foot backwards against the ground and the reaction is the ground pushes your foot forward with an equal amount of force.

how is work done

work is done on an object via the application of force over a set distance.

energy

the ability to do work

force

a push pull or twist that affects an objects motion

work

the application of a force over a distance it is measured in joules (J)

work equation

w=fs

work=force x distance in meters

what work does falling objects have on them

gravitational force is working on falling objects

why is work required

work is required to move an object through gravity

objects lifted through gravity require what

gravitational potential energy (Ep)

gravitational potential energy formula

Ep=mgh

potential energy=mass x gravitational field (9.8) x height

what is the change in potential energy as it is lifted through gravity

the potenetial energy gets higher and bigger as it is lifted higher.

what is kinetic energy

the energy of movement any moving object has potential energy the faster an object is moving the more kinetic energy it has it is measured in joules (J)

kinetic energy formula

Ek=1/2mvsquared

kinetic energy=1/2 x mass x velocity squared

what does more kinetic energy in an object mean

the more kinetic energy that an object has the more work it is doing

law of conservation of energy

the total energy is maintained in energy transfers and transformations

how does the law of conservation of energy predict values of kinetic energy in a falling object

as an object falls it loses potential energy and gains an equal amount of kinetic energy

t

time, in seconds

s

displacement/distance in meters

a

acceleration (m/s) if it is gravity doing the acceleration it will be 9.8 m/s

Vf

final velocity/speed (m/s)

Vi

Starting/intial velocity/speed (m/s)

kilometers per hour to meters per second

divide by 3.6