Core Physics – Energy

L/O :- To know the properties of waves and be able to explain reflection

“Mirror, Mirror on the wall”

Exam Date -

Quick Quiz - What do you remember from last lesson?

• Draw and label a wave• What is the use of a step-up transformers • What is the equation for working out the

speed of a wave?• How does a coal power station turn the

turbine to spin the generator?• What is the equations for working out

efficiency?• What are the 2 different types of wave?

Give an example• How do you work out the pay-back time

for insulation?• What are the pros and cons of wind

energy?• Where are step-up transformers used?• How does increasing the volume of a

sound affect the wave?

2 Sec

AB

C

1.Which wave has is the quietist? Why?

2.Which wave has the highest pitch? Why?

3.Which wave is the loudest? Why?

4.What is the frequency of wave C? Why?

All waves can do 3 things

Reflect

Refract

Diffract

Do you notice anything strange about this picture?

Can you explain why this is?

What do you know

about reflection?

End

TASKThere are a number of objects around the room. You are going

to be asked a) What do you notice?b) How does it work?c) What does it tell you about reflection?

You will need to fill out a sheet in pairs. You should take it in turns to fill out the sections. You will then be asked to feed your ideas

back to other groups

www.A6training.co.uk

2 Minute Timer

2:001:591:581:571:561:551:541:531:521:511:501:491:481:471:461:451:441:431:421:411:401:391:381:371:361:351:341:331:321:311:301:291:281:271:261:251:241:231:221:211:201:191:181:171:161:151:141:131:121:111:101:091:081:071:061:051:041:031:021:011:000:590:580:570:560:550:540:530:520:510:500:490:480:470:460:450:440:430:420:410:400:390:380:370:360:350:340:330:320:310:300:290:280:270:260:250:240:230:220:210:200:190:180:170:160:150:140:130:120:110:100:090:080:070:060:050:040:030:020:01End

Solar TubesWhat do you notice?

How does it work? 

What does it tell you about reflection? 

Periscope

What do you notice?

How does it work? 

What does it tell you about reflection? 

Glass and Candle What do you notice?

How does it work? 

What does it tell you about reflection? 

Solar KettleWhat do you notice?

How does it work? 

What does it tell you about reflection? 

Mirrors and spoons What do you notice?

How does it work? 

What does it tell you about reflection? 

Da Vinci Writing What do you notice?

How does it work? 

What does it tell you about reflection? 

21/04/23

Reflection

Incident ray

Normal

Reflected ray

Angle of incidence Angle of reflection

Mirror

Angle of incidence = Angle of Angle of incidence = Angle of reflectionreflection

21/04/23

Using mirrors

Two examples:

21/04/23

Finding the Critical Angle…

1) Ray gets refracted

4) Ray gets internally reflected

3) Ray still gets refracted (just!)

2) Ray still gets refracted

THE CRITICAL ANGLE

21/04/23

Sound can also be reflected

Bats use echoes to locate insects. They

time how long the echo takes to come back and use that to locate the

insect

• An Echo is a reflected sound wave

Echolocation is also used in the shipping industry

but remember Sound in air = 330m/sSound in water = 1500m/s

What have you learnt?

• Do you know what 3 things all waves can do?

• Do you know what the law of reflection is?

• Do you know what the reflection of a sound wave is called?