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Junior Cert: Force, Work and Power

Syllabus
       
OP15
Define and give the units for work, energy and power
State the relationship between work and power, and perform simple calculations based on this relationship
OP 4
Understand the concept of force
 
  Who knew concussion was an example of Newton's first law of motion YouTube. 4 mins  
  Explain it to me: Concussions link YouTube. 3 mins  
Recall that the newton is the unit of force      
Describe forces and their effects      
       
OP 5
Friction
     
  Microscopic simulation Friction between two rough surfaces, from absorblearning.com
4 Star
    And from a smooth surface 3 Star
    The effect of ball-bearings in reducing friction 4 Star
    The effect of lubrication in reducing friction 4 Star
  Rub the two books against each other and note the temperature
3 Star
         
  Nice counter-intuitive demonstration Interweave the pages from two books and then try to pull them apart. Youtube. 2 mins
4 Star
    How about using military tanks to pull them apart? Mythbusters on YouTube. 6 mins 4 Star
    Can this friction force lift a car? Vsauce find out on YouTube. 6 mins 4 Star
  Interactive simulation Set the coefficient of friction and then give the book a shove
3 Star
  You do know what happens when friction disappears Car pile-up caused by ice. Youtube. 5 mins. 3 Star
         
  Did you know that the primary function of saliva is to act as a lubricant? Take the cream-cracker challenge to find out more. 7 minutes from YouTube, but more fun to try it in class yourself.
4 Star
         
  Forces always act in pairs, and if one object pushes or pulls on another object, the force on both will be the same. This actually seems very strange - watch this YouTube clip and follow the instructions in relation to predicting in advance. 1 min. 5 Star
         
OP 6

Investigate the relationship between the extension of a spring and the applied force

     
  Excellent overview on why we have graphs Includes advice on drawing best-fit lines. Powerpoint 4 Star
  Demonstrating the mandatory expt YouTube 3 mins 3 Star
  An interactive Force-Extension graph for a piece of elastic From absorblearning.com
4 Star
  Simulation of the experiment. Attach different weights and measure the extension. From Phet.com
5 Star
  Simpler simulation, but less realistic From absorblearning.com
4 Star
         
OP 7
Weight is the force of gravity and weight varies with location      
  World's Roundest Object! Redefining The Kilogram YouTube. 12 mins. Brilliant, but a bit advance for first years. 5 Star
  Did you know that weight varies even around the Earth? To raise awareness, a Bavarian scale manufacturing company, is sending an acrylic garden gnome named Kern around the world, accompanied by a set of scales.
From New Scientist
4 Star
         
  Weightlessness and space Short video - Register or test-drive 5 Star
  Why are astronauts weightless? Short answer - they're not. YouTube 4 mins 4 Star
  Why doesn't the space shuttle fall to Earth? Cool explanation. youtube. one minute 5 Star
  Another viewpoint This time from an astronomer. Youtube. Two minutes 4 Star
  What's it like to experience weightlessness? An astronaut gives his experience. Youtube. 3 minutes 4 Star
How do they go the toilet? You know you want to know. Youtube. 2 minutes 4 Star
  Why zero-gravity bowling will never catch on link Cartoon 3 Star
  What happens when you wring a washcloth in space? Youtube. 3 minutes 5 Star
         
  Accelertion due to gravity      
  Which falls faster - a cannon-ball or a feather?
What about if you try it in a vacuum?
Place a vacuum jar over Galileo as he drops a canon-ball and feather from the leaning tower of Pisa 5 Star
  Brianiac try it as only they can link Youtube. 3 minutes 4 Star
  feather and hammer drop on the moon Youtube. 2 minutes. Poor quality 3 Star
         
OP 8

Mass in kilograms multiplied by 10 is approximately equal to weight in newtons on the surface of the earth

     
  When is a kilogram not a kilogram? Link Blogpost from thinkforyourself.ie  
  Famous documentary about Isaac Newton - he wasn't as wonderful a character as textbooks often make him out to be Link YouTube. 52 mins. Newton's Dark Secrets 5 Star