2_3 force mass acceleration

7/27/2019 2_3 Force Mass Acceleration

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Resultant forcesFind the resultant force on these objects.

2.3 Force and acceleration29 October 2013

10N 5N 10N 20N

10N

30N

10N 10N

15N


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5N 30N

20N 5N


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LOsBe able to explain how force and mass affectacceleration

V Majer


The F18 Hornet aircrafttakes off at 140mph andweighs almost 30 tons.

Aircraft carriers are notlong enough for it to reachthis speed. Steam catapultshelp the launch.
http://www.youtube.com/watch?v=VVdvTof186w&NR=1


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How are force and acceleration connected?

1. Set up apparatus as shown.2. Attach a 50g mass to the

end of the string.3. Time how long it takes forthe trolley to travel 1metre.

4. Add another 50g andrepeat.

5. Take 5 different readings.

Trolley String pulley

Weight

Ramp

Diagram

Method

Weight (N) Time (s)

Results


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Acceleration is proportional to force

The mass pulls the trolley along thetrack, and it accelerates because of

_______.

If we increase the weight (a force),acceleration will ______.

Force

Acceleration

Complete thissketch graph.


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Acceleration is proportional to force

The mass pulls the trolley along thetrack, and it accelerates because ofgravity.

If we increase the weight (a force),acceleration will increase.

Acceleration

Force Force increases sothe accelerationincreases.


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Acceleration is inversely proportional to mass.

If this time we change the mass of theobject being pulled, increasing it by 1kg.

The following graph is obtained.acceleration

mass


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You should be able to:All

Be able to explain that if force is increasedacceleration is increased and if Mass is increased then

acceleration is decreased.Most

Be able to use equation ( if given)

Force = mass x acceleration.

Check


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Practical.

A trolley rolls along a track.

A ticker timer is used to calculatespeed and acceleration

Different forces are use to start itmoving

Then different masses are added andthe experiment is repeated


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Results

1N 2N 3N1st reading (taken at0s)

0m 0m 0m

2nd reading (taken at1s) 1m 2m 3m

Change in speed (m/s)

Acceleration (m/s)

Copy and complete


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Question

What is the relationship betweenthe acceleration and the force?(use

an ER...ER relationship)


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Results

1kg 2kg 3kg1st reading (taken at 0s) 0m 0m 0m

2nd reading (taken at1s)

1m 0.5m 0.33m

Change in speed (m/s)

Acceleration (m/s)

Copy and complete


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Question

What is the relationship betweenthe acceleration and the mass? (

Use an ER............ER relationship)


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We have discovered:

1. As force increases so doesacceleration. (This is common sense,the harder you push something, thefaster it moves!)

2. As weight increases, accelerationdecreases. (Again, this isnt rocket

science! If somethings heavy its hardto shift!)

Copy


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Mathematical relationships

Force = Mass X Accelerationnewtons kilograms metres/second

FM XA

Copy

2_3 force mass acceleration

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