Motion

Motion refers to something that is moving.

Write down 10 things that move!

What makes these things move ?

Order them into fast objects and slow objects

What would happen to a golf ball left in a place ??

it will not move because there is no net force on it

What would happen to an asteroid flying through space ??

there is no force to slow it down and so motion will continue

Newton's First Law

states that an object at rest tends to stay at rest and

that an object in uniform motion tends to stay in uniform motion

unless acted upon by a net external force.

When an object is moving they do slow down ......

so therefore ..... there must be an external force applied

what is the name of the external force that slows everything down ??

Friction

How could you measure friction ??

How can we describe something that is moving, that has motion ?

What adverbs go with moving Blankyty blank

___________ moving _____________

So what does something moving fast mean ? or something slow, what is the difference ?

Time ? Is there any other measurement involved ?

Distance

Can we think of the units of speeds we have heard of ...... km/h

What does km stand for ?

What does h stand for ?

What does the / stand for ?

so what does that mean

Solve the following

A man cycles 25km in 1 hour, find his speed ?

A boy walks 2km to the center in 30 mins, find his speed ?

A woman drives 220 km to Galway, it takes her 2 hours find her speed ?

A girl runs the Hartstown 5k park run in 20 mins find her speed ?

Usain Bolt runs the 200m race in 19s find his speed ?

It take light from the sun 8 minutes to reach earth, light travels at 299,000,000 m/s how far away is the sun.

A man in an electric car can only travel a maximum speed of 55 km/h how long will it take him to get to Cork, 275 km away ?

okay it took the 1st Miner 30 mins to get out of the mine a distance of 624m calculate the speed of the phoenix 2

by the last few survivers it was down to 10m33s

Velocity is speed in a given direction

Calculate the velocity and acceleration in the following applets

http://vnatsci.ltu.edu/s_schneider/physlets/main/constvel1.shtml

http://vnatsci.ltu.edu/s_schneider/physlets/main/constaccel1d.shtml

You have to be able to draw or at least understand (interpret) motion graphs

http://physics.info/motion-graphs/

some look at the right graphs here

http://www.scienceunleashed.ie/Games/Timedistancespeed.swf

Acceleration is the rate of change in Velocity

Acceleration occurs when a bodies speed Increases or Decreases

When the speed / velocity decreases the acceleration is given a negative value.