Lesson 1

Unit Title:  Pressure and moments
Caretaker: H Wain

Unit No   
9L

Lesson Title: Pressure

NC Ref: 

Objectives:    

MK - Pressure is the amount of force acting on a certain area.  The size of the force and the size of the area affect the size of the pressure.
SK - The formula for pressure ie Pressure = Force / Area. The unit of pressure as N/cm², or N/m² (Pascal)
CK - How to rearrange this equation.

Lesson outline: Horsforth Commentary

Starter activities: Using animals worksheet.  Only hard copy available at present, ask technicians.  It is Christmas.  The ark is stuck on ice.  The birds are on strike.  Noah needs to send a message and get help.  Who will he send?  The animals on the sheet volunteer but only if they can go on their Christmas presents.  The ice will break if more than 7N force pushes down on each square centimetre.  Who should go?

Ask all students to predict and give a reason - this always generates discussion around weight / force and area.  The sheep in boots is the most likely candidate!

Main course:

HIGH ability - can use second sheet to work out whether they would be able to go in the shoes they are currently wearing. Newton weighing scales and squared paper needed to work out area of their shoe.

LOW ability - use idea as a basis for discussion then show some simple demonstrations. At each station complete a sentence which uses all three of the words force, area and pressure.  They simply need to decide whether each is large or small and then specify the outcome.

example - "the drawing pin sticks into the board because the force is concentrated on a small area so the pressure is large."

Examples: Drawing pin into notice board, stilletos and trainers into sand, holding a 10kg mass using a looped thin piece of string and a thick cord, slicing a tomato with a sharp knife and a blunt one.
 

ALTERNATIVELY - could do an investigation with wooden blocks of different sizes or different weights as dependent variable and trays of sand into which indentations will be made as dependent variable.

Plenary: W/S 9La/2  Pressure links

Timings:

Homework Suggestion: Higher W/S 9La/4, Lower give them a question such as "why do football boots have studs" and look for a full answer of the style discussed in lessons

Resources: Bathroom scales measuring in Newtons, squared paper.  Possibly sand trays, blocks of wood of various sizes, metre rules, 1kg masses.

Lesson 2 

Unit Title:  Pressure and moments
Caretaker: H Wain

Unit No   
9L

Lesson Title: Pressure all around

NC Ref: 

Objectives:    

MK - How pressure is caused in liquids and gases
SK - That gases can be put under pressure, that pressure increases with depth.
CK - 

Lesson outline: Horsforth Commentary

Starter activity:

Main course: Demonstrations: 

1.Pupils put on a disposable plastic glove and place hand in bowl of water.  Should feel pressure in all directions.

2.Use spouting can with three holes at top, middle and bottom. Note how far water spurts

3."Suck" up water in a syringe or straw and explain that it actually air pressure pushing water up syringe

4.Re-demonstrate the model lung and diaphragm - good chance to revise breathing

5.Magdeburg hemispheres and vacuum pump.  Ask Gilbert to be an able assistant

6.Blow the lid off the top of a treacle tin by heating it

7.Revisit collapsing can either with vacuum pump or coke can and water.  If go for latter opportunity to revise changes of state.

Plenary: W/S9Lb/2
 

Homework Suggestion: W/S9Lb/4
 

Resources: plastic gloves, washing up bowls, spouting can with rubber bungs in spouts, straws and syringes, model lung, Magdeburg hemispheres, vacuum pump, treacle tin, coke cans.
 

Lesson 3 

Unit Title:  Pressure and moments
Caretaker: H Wain

Unit No   
9L

Lesson Title: Levers

NC Ref: 

Objectives:    

MK - Levers are simple machines that forces can move an object around a pivot
SK - How simple levers work including in human body so re-visit antagonistic muscles etc
CK - How levers are used in some machines.

Lesson outline: Horsforth Commentary

Starter activity:  Ask a student to open the door from the outside first by pushing at the handle and then by pushing near the hinge.  Why are door handles on the opposite side to the hinge?  Ask a student to open a can of paint with their fingers then  with a screw driver,.
 
Main course: Investigation - How does the length of a lever affect the force you need to lift a load?  Based on worksheet 9Lc/1.  I would use a Forcemeter to pull on the opposite side to the sand bag and read off the result.

Make a model arm

and discuss antagonistic pairs.  Muscles can only pull.

Plenary:  Revisit the door and paint question.  Ask all students to write down an explanation using the key words effort, load, pivot and distance.
 

Timings:

Homework Suggestion: Give 3 examples with explanations and diagrams of levers in action
 

Resources: Metre rules, 10N, Newtonmeters,  1kg sand bags, metre rules, pyramidal block of wood to act as a pivot, 100g slotted masses, thick cardboard, split pins, thin string, scissors.
 

Lesson 4 

Unit Title: 
Caretaker: 

Unit No   
 

Lesson Title: Moments

NC Ref: 

Objectives:    

MK - HIGHER LEVEL ONLY
SK - That a moment is the turning effect of a force about a pivot and is calculated by force x distance.  If an object is to balance then the total moment kclockwise must equal the total moment anticlockwise.
CK - 

Lesson outline: Horsforth Commentary

Starter activity: Ask 2 students to hold a 1kg mass still on a horizontally held clamp stand.  The first has the mass close to their had, the other has it right on the end.  Revisit later.

 
Main course: Do not give formula for moment yet.  Using plastic see-saws, students have to place a varying number of marbles or slotted masses at ONE particular groove on the see-saw.  They must then use a DIFFERENT number of marbles in A SINGLE groove  at the other side that causes it to balance (or closest to it).  Don't spend the entire lesson fiddling about with the balance point.

Table headings will be

Once a number have been done, see if they can work out the rule for balancing.  In the past I have put results that work onto the board as I have visited each group so that a "perfect" set of results are available for class discussion of the principle of moments later.  Give notes and units.  The MYSTERY column will eventually contain "marbles x groove" or better still "force x distance from pivot"

Plenary:  Use W/S 9Ld/4 to go through worked example and then they can try the rest.
 

Timings:

Homework Suggestion: Any SATs questions on moments or W/S 9Ld/6.  A lot of practice is needed on this.
 

Resources: Plastic see-saws, marbles, 10g slotted masses