Landing Time of a Parachute – Air Resistance

Creative Commons image from Wikimedia

Learning Intention: To investigate the effects of forces and to design, carry out and report on a simple practical experiment with controlled variables.

Success Criteria: Students will design and carry out an experiment to find out the effect of different factors (mass of object, size of canopy or shape of canopy) on the landing times of a parachute with a toy (Barbie, toy soldier or Lego man) attached. They will vary only one factor, collect data to gain an average of at least three ‘jumps’  and record their results in a table. Students will complete a report of their investigation that includes Aim, Method, Materials, Results, Discussion and Conclusion.

When objects are dropped from a height, gravity is not the only force acting upon them. You would feel the other forces if you jumped from a plane, as air resistance. The picture above shows the design of the world’s first human parachute – can you think of any animals use air resistance to aid movement?

Your task this week is to find out the effect of one of the following variables (something that changes) on the landing time of a parachute. You can use cotton or nylon thread to attach the parachute and drop it from at least two metres.

  • Mass of the skydiver (use a Barbie doll, toy soldier or Lego man with weights added)
  • Size (area) of the canopy (use plastic freezer bags or garbage bags)
  • Shape of the canopy

Make sure that only one of these factors changes and repeat each trial at least three times. Draw up a table to record your results.

 

Year 7 Science: Forces

Magnet and Compass

Click to Run

 

 

Interactive Learning Object from PheT, Colorado

Learning Intention: Students will understand that forces can start motion, stop motion, change the speed or direction of motion, change the shape of an object or have no effect at all. They will be able to distinguish between contact forces (friction, buoyancy, surface tension, mechanical forces) and non-contact forces (magnetic and electric forces).

Success Criteria: Students will create a 60 second science video that demonstrates their understanding of forces.

This term Year 7 students will continue learning about forces, using simple experiments with magnets, water, weights and wires. We will also use some online and netbook tools to learn about forces. Click on the interactive above to enter the learning object. Read more about the magnetic field of the earth at BBC Bitesize: Magnetic Fields.  Do-it-Yourself magnetic levitation at You Tube. Everything you ever want to know about magnets from the Cool Magnet Man. 

Your task this week is to produce a 60-second science video that demonstrates your understanding of forces – choose one of the forces we have discussed (magnetic, friction, static-electric, buoyancy, surface-tension, gravity, muscular and mechanical forces). Create a story board and a script before you borrow the cameras and start filming and editing. You will need to register on the site using a username and password before you upload your video.

60 Second Science Video Competition

matchstrikine

What forces are involved when striking a match?

Learning Intention: To work in a team to develop the skills required to produce a short video and to describe how an object moves in terms of the forces involved.

Success Criteria: A successful video will clearly explain how objects move using scientific terminology and be entered into the “60 second science” video competition.

Over the next week you will be planning and producing a minute-long video for the annual “60 second science” video competition. You can see past examples of student videos on the website. Your task is to explain how an object moves in terms of the forces involved. So, the title of your movie could be one of the following:

  • How does a boat float?
  • How does a plane fly?
  • How  can you do flips on a skateboard?
  • What forces are involved in kneeboarding at the beach? (Good work Tobie)
  • How can you skate fast on ice? (Excellent example Alex)
  • What forces oppose gravity? (Great idea Elektra, Jade and Ruby)
  • How can you simulate zero gravity on earth? (Good one Kaylee!)

Your first step after deciding on a topic to investigate is to create a storyboard that shows each of the scenes in your video. You can use an A3 paper folded into eight sections or create one online. Make sure all the images and music you use are Creative Commons, Copyright Free.

Forces in Action

banana_boat

Image Source

Learning Intention: Understand the motion of objects in terms of  gravity, magnetic and electrostatic forces, bouyancy, friction and surface tension.

Success Criteria: You will be able to describe how things move using simple combinations of forces. For example, “A boat floats because the bouyancy forces are greater than the forces of gravity”.

Year 7 students have started a unit of work about how forces can:

  • Start motion
  • Stop motion
  • Change the speed
  • Change the direction
  • Change the shape of objects or
  • have no effect at all. 

Your task is to produce a concept map using bubbl.us,  showing contact and non-contact forces, including pictures as examples of each force. I have used “Arthur’s Clip Art” to get some free images to illustrate each of the forces. You could also use “Fotopedia” or “Creative Commons Search” to find images free from copyright restrictions.

Forces_mindmap