Core Physics – Energy

L/O :- To understand the dangers of electromagnetic radiation

“Slip, slop slap”

Exam Date -

Quick Quiz - What do you remember from last lesson?

• Write out the electromagnetic spectrum from longest to shortest

• What is the law of reflection?• What is the equation for working out the

speed of a wave?• What happens to a light ray when it

travels from air through glass? Why does this happen?

• What is diffraction?• 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?• How does increasing the volume of a

sound affect the wave?

What do you think caused all of these?

The Electromagnetic Spectrum

Gamma rays

X-rays Ultra violet Visible light

Infra red Microwaves

Radio/TV

Each type of radiation shown in the electromagnetic spectrum has a different wavelength and a different frequency:

High frequency, _____ wavelength

Low frequency, _____ (high) wavelength

γWhich of these are the most

dangerous?What affects

how dangerous

the wave is?

The shorter wavelengths and higher frequency

wavelengths can cause the cells to MUTATE.

This can lead to CANCER

What part of the electromagnetic spectrum causes all of these types of

cancer?

What can you do to

help prevent all of these?

Do In the UK really need to worry about the

sun??

• Give 2 things, other than skin cancer that exposure to the sun can cause

• What are the 2 types of rays from the sun that can cause skin cancer?

• Name 3 things that you should do to prevent UV skin damage?

• Give 4 possible warning signs of skin cancer?• What is it most important thing to look for in a sun cream?• What is the UV index?• When is it most important to stay out of the sun?• What type of skins are most likely to be affected by skin

exposure?• What has lead to an increase in the UV rays reaching us

from the sun in the last 15 years?

Use the articles to answer these questions

Journalist Cornelia Dobb knew about the dangers of tanning; she'd even done a feature on skin cancer, but she never really imagined it would affect her. Here she tells her story. It looked like a beauty spot, perhaps a little blacker than its neighbours, but it certainly didn't look like a killer. It had been there for just over a year, although I had no recollection of when it first appeared. It didn't change shape, size or colour, nor did it bleed or itch, so I put it to the back on my mind. A year later, I was sitting chatting to my GP about malaria tablets. I was about to move to Cambodia for two years with my husband-to-be, a BBC correspondent. It was a hot summer's day and I sat cross-legged with one bare foot resting on the opposite thigh. 'Do you know you have moles on the soles of your feet?' she interrupted. She sounded alarmed. 'Yes', I said. 'I've had them for years. I've got them on the palms too, but they're not doing anything they shouldn't.' She seemed satisfied that there was nothing to worry about, and returned to the more pressing matter of malaria and rabies. Up against life-threatening diseases contracted from mosquitoes, bad water, pigs and mad dogs the sun didn't seem to pose much of a threat. A couple of weeks later, I received a letter from that same GP. 'I've changed my mind about those moles,' it said. 'Given that you're about to move to the tropics, I'd definitely get them checked out.' With incredible efficiency, she had even booked me an appointment. I looked at the date: 4pm, 22 July 1994 - less than 24 hours before I was due to walk down the aisle in a Dorset church. I cancelled the appointment. After our honeymoon, my husband, Jonathan, left almost immediately for his new posting in Cambodia. I would join him when I had organised the letting of the house and packed everything up. There were so many loose ends to tie up; I had lists of things to do. At the bottom of my health checklist was (if I get time) to re-book that appointment at the Chelsea & Westminster Hospital dermatology department. Somehow, I did get time. I went along a couple of weeks before I was due to get on the plane to Cambodia. The consultant checked my feet and hands and told me not to worry about them: they looked perfectly harmless. Just as I thought. I was walking out of the door. I stopped and said, 'Just before you go, would you mind taking a look at this one on mu tummy? The dermatologist told me to come back that afternoon to have it removed. It wasn’t the response I had expected or wanted. It was inconvenient, now I had to hang around all day. Grumpily, I returned to the ward, was ushered into a treatment room and on to the bed. My tummy was numbed with a local anesthetic and then a little eye-shaped patch was carved out of it and popped in a jar. The hole left behind required one stitch and that was it. They said they'd contact me if there was any problem with it, but if not, bon voyage! I didn't expect to hear from them again.

A week later, with packing boxes all around me and tenants due to move in any minute, there was a message on the answering machine. The voice was matter-of-fact. I had a Malignant melanoma. I didn't hear anything else. It was cancer; it was fast; it was uncontrollable and probably deadly. I had got it. Would I die? 'Someone’s looking after you,' said the voice on the other end of the phone. 'If you hadn't discovered this by now, it's unlikely that you would have made it back from Asia.' I returned to the dermatology ward the following morning. This time, I didn't resent the hanging around; I was brimming with gratitude that they had found this thing. I went to the same little room with the same kind Scottish nurse. There was much more anesthetic this time, several injections, and the area they cut was broader and deeper. They needed to do a biopsy to see if the melanoma had spread downwards. I left with eight stitches where a week before there had been just one. I would have to wait ten days to know if the cancer had spread. That night I went to bed feeling incredibly alone with my uncertainty and fear. I couldn't sleep. I sat bolt upright in the middle of the night, put the light on and started poring over every freckle, imagining that it was sending cancerous cells into my bloodstream. I recounted in my mind all those holidays to Spain, France and Greece in my teens and 20s, when the thing to do was to burn yourself for the first couple of days to get that golden tan going and then have it all peel off on the plane home. I'd been trekking in Thailand with no protection, arguing in my head that I wasn't lying on a beach, therefore I couldn't burn. I'd hitchhiked my way around Australia with a bottle of SPF4. It was all my fault. I had been incredibly lucky. The melanoma was in situ, on the surface, and hadn't spread. I had been saved. It felt as though somebody, somewhere had been watching over me. I could so easily have not made it to the hospital. I could so easily have walked out the door without mentioning the mole on my stomach. I could have gone to Cambodia, still a sun worshipper. I could have died. Three years on, and I'm still a little paranoid about new moles appearing. I'll suddenly get fixated with one particular mole and it'll bother me for weeks until I get a specialist to check it out. I feel like I'm on a mission now when I see red bodies splayed out by a pool, roasting themselves in oil under the midday tropical sun. I have an overwhelming urge to tap them on the blistering shoulder and warn them, because, until three years ago, I was just like them. I still love the feeling of sunshine on my face and I haven't quite managed to convince myself that pale is beautiful. But I know now that when I'm tanned, I might look and feel healthier for a couple of weeks, but in the long run, I'm actually risking my life.

Task - Design a poster / TV advert to explain how people

can protect themselves against UV radiation

What have you learnt?

• Do you know which are the most dangerous UV rays • Can you explain how high frequency Electromagnetic waves affect your cells?• Can you give 2 ways you can protect yourself against harmful UV radiation from the sun?