Radios, Respect, and More Radios

Positive/Negative/Neutral Objects - How are they different? Positive: has fewer electrons than protons Negative: Has more electrons than protons Neutral: has equal numbers of protons and electrons Laws of Electric Charges - What are they? How are they applied? Like charges repel, opposites charges attract, charged AND neutral objects attract Induced Charge Separation - Explain this process. A shift of the position of electrons when a charged object is brought near it. If the charged object is positive, the electrons will move toward it. If the charged object is negative, the electrons will move away from it. Charging by Friction (What is happening with the charges? - Know electrostatic series examples) Process in which objects made from different materials rub against each other, producing a net static charge on each object. When charged by friction, one material will have a stronger attraction to electrons and will pull the electrons off the other material Charging by Conduction (Be able to explain what the electrons are doing) Charging by contact with a charged object. An object that becomes charged by contact always gets the same type of charge that is on the object that charges it. Grounding (Be able to explain how it happens) A method of removing static charges from an object. Electrons from the ground move up to the charged object. If the object is negative, electrons leave the object. If the object is positive, electrons enter the object. The ground always remains neutral Conductors/Insulators/Semiconductors (Know examples for each and characteristics) Conductor: A material that allows electrons to flow through it easily. GOOD CONDUCTORS: Silver, copper, gold, aluminium, magnesium, iron, usually metals Insulator: A material that prevents electrons from flowing through it. Plastic, wood and glass are examples. To prevent electric shocks, conductive wires are wrapped in insulators. Semiconductors: Have special properties that make them fair conductors, they are the foundation of modern electronics, including radios, computers and telephones. Charging by Induction (How do we induce a PERMANENT charge?) You can permanently charge an object using induction by attaching a conducting wire to the neutral object that goes to the ground Electric Discharge - What causes it? Know everyday examples. How is lightning formed? When two objects that have a charge imbalance are brought close together or come in contact with each other, electrons are transferred rapidly. Electrons move from the object with a more negative charge to the object with the less negative charge. Lightning occurs through an imbalance of charge between clouds and the ground. Negative charge at the bottom of a cloud repels the electrons at the earth's surface which move away, causing the ground to become positively charged Current Electricity: Refers to the electrons that flow in a controlled way through a conductor Forms of Current Electricity - Alternating Current (AC) vs Direct Current (DC) - How do they differ? AC: Electrons move back and forth, alternating their direction. produced in generating stations and is then distributed over long distances ex. Something plugged into a wall outlet

Important Preparations Before an Earthquake Strikes • Follow the structural design and engineering practices when constructing a house or building. • Evaluate the structural soundness of the buildings and houses: strengthen if necessary. • Be aware of the earthquake evacuation plans for all of the buildings you occupy regularly. • Strap or bolt heavy furniture and cabinets to the wall to keep them in place. • Breakable items, harmful chemical, and flammable materials should be stored properly in the lowermost secure shelves • Prepare and know where fire extinguishers, first aid kits, alarms, and communication facilities are located and learn how to use them beforehand. • Pick safe places in each room of your home, workplace, and school and practice doing drop, cover, and hold.Essential Things to Do While an Earthquake is Happening • Stay calm. • Duck under a sturdy desk or table and hold onto it. Protect your head with your arms. • If there is no sturdy furniture, sit on the floor in a corner next to an interior wall and cover your head and neck with your arms. • Move away from glass windows, sliding doors, shelves, cabinets, and other heavy objects. • Grab anything handy to shield your head and face from falling debris and splinting glass. • Stay indoors until the shaking stops. If you must leave the building. use the stairs rather than elevators. • Stay away from trees, power lines, posts, and concrete structures and proceed cautiously to an open area. • Move away from steep. slopes, which may be affected by landslides. • Move quickly to higher grounds since tsunamis might follow • Pull over to a clear location and stop. Avoid bridges, overpasses, and power lines, if possible. • Be updated about disaster. prevention instructions from battery operated radios.Essential Safety Measures After an Earthquake • Check yourself and others for injuries. • Do not panic. • Expect and prepare for aftershocks. These aftershocks may be weaker but they may sometimes cause more damage than the major earthquake. • Look for emergency supply kits. They should include food, water, medication, clothing, and other things you may need. • If you need to evacuate, leave a message stating where you are going • Do not enter damaged buildings since they might have weakened foundations, increasing their susceptibility for collapse. There can also be a lot of falling debris. • Do not use elevators • Check water and electrical lines for damages. Turn the main switch off to avoid any incidences of electric shock • Look for and extinguish fires to reduce their chances of spreading. • Avoid fallen power lines. • Tune in to radio broadcasts and be updated on disaster prevention instructions.

The following days are a jumble of gunfire, digging, gobbled food, soldiers running in and out of the forest in small groups, distant explosions, stray shells, bandaged heads and unexpected lulls. On the very first day, before dawn, I am ordered into one of the newly dug trenches. I huddle there, squeezing my magic buttons and singing songs to the dog. When the fighting stops, the dog disappears, but a new companion takes his place. A strange little soldier crawls along the trench toward me. ‘Private Sasha!’ he cries. ‘I’ve been looking for you all day long!’ He’s old, like a grandfather, a dedushka. He has a black patch over one eye, a tape measure around his neck and a row of pins threaded into his sleeve. Hanging from his belt is the most enormous pair of scissors I have ever seen and I wonder if he uses them as a weapon. He doesn’t tell me his name, so in my head he becomes Dedushka. Dedushka squats, cups his hand to his ear, peers over the top of the trench and smiles. ‘It’s safe to be upright . . . for now.’ He helps me to my feet, dusts me off and commands me to stand as tall and straight as I can. Then he measures me. Everything from head to toe – even my toes! He writes numbers in a little notebook, strings his tape measure back around his neck, salutes and hurries away. It’s all very strange, and I wonder if Dedushka has been bumped on the head during the battle and is now a little bit muddled. I should have given him a hug before he left. I chase after him but stop when I’m hit by a shovelful of flying dirt. Sleepy Bear is digging a cave! ‘Are you going to hibernate?’ I ask. Sleepy Bear chuckles. ‘No, although that would be wonderful! I could do with a lo-o-o-ong sleep.’ He sighs and closes his eyes. He doesn’t open them again and I realise that he has gone to sleep. Standing up! I shake his arm, and he opens his eyes and keeps talking. ‘No, I’m not hibernating. I’m digging a little nook where I can sleep and eat. I’ll hang up my raincape as a door that can open and close so it feels just like a real home . . . except for the lice . . . and the bad smells . . . and the bombs that make the walls shake and crumble.’ He points further along the trench to where other soldiers are digging. ‘We’re all making little houses in the ground.’ ‘Like rabbits and moles,’ I say. Sleepy Bear chuckles. ‘Yes! And soldiers who need to hide from German bullets and bombs.’ He stops digging to roll a cigarette. ‘Should I be making a house?’ I ask. ‘I want to hide from German bullets and bombs, too.’ Sleepy Bear flops to the ground, lights his cigarette, closes his eyes and takes a deep puff. I wait for him to answer, but, instead, he begins to snore! I poke him in the side. He snorts and he murmurs, ‘I think someone has already built you a house, Sasha. Keep going along this beautiful village street and you are sure to find it.’ He falls asleep once more. I kiss his dusty cheek and whisper, ‘Thank you, Sleepy Bear.’ A little way along, I see Cook in a cloud of smoke. He has lit a fire, right here in the middle of the trench, and is stirring a cauldron full of kasha. He squats as he stirs. ‘What are you doing?’ I ask. ‘Cooking supper, of course!’ he cries. ‘But why are you doing it here?’ Cook points his spoon at the ground above the trenches. ‘Because if I do it up there, my pot will be filled with holes from German bullets and all of the kasha will leak out onto the ground. It’s bad enough that our supplies can’t get through German lines and there’s nothing to cook but buckwheat for kasha. But if we lost the kasha, too . . .’ ‘Hungry soldiers,’ I say. Cook nods. ‘And grumpy!’ ‘Like Boris!’ I gasp. ‘Even worse,’ warns Cook. I picture the kasha pot full of bullet holes. And then I realise that if the kasha pot were full of holes, then Cook would be, too. I wrap my arms around Cook’s neck and say, ‘I think this is a very good place for cooking our supper.’ I kiss his smoky cheek and run along. At the end of the trench, I find the biggest hole of all. It’s wide and deep and as busy as a beehive in a blossom tree. Above, a group of soldiers is rolling logs into place for a roof, while below, typewriters rattle and pencils scratch and papers flutter and voices crackle out of five different radios. Their words tangle together to tell a strange wartime fairy tale about German guns and a loving father called Stalin and a Red Army regiment that is lost in the deep, dark forest and a wicked beast called Hitler and a delivery of vegetables that was hit by a bomb and blown into a million tiny pieces too small even to make soup. In the middle of it all, wrestling with a rumpled map, his rifle still slung over his shoulder, is Major Scruff. ‘Major Scruff!’ I run and jump into his arms. ‘Is this our new home?’ ‘Yes, Sasha. I suppose it is.’ ‘Is it safe from German bullets and bombs?’ I ask. He stares at me. ‘Were you scared in the trenches today, Sasha?’ ‘No,’ I reply. ‘I had magic buttons and a dog and some songs to sing. Were you scared in the forest, Major Scruff?’ ‘Yes,’ he says. ‘Poor Major Scruff!’ I press my hand against his cheek. The dark, rough stubble is grubby with grit and his eyelids are taking a long time to open after every blink. ‘You need a shave and a nap!’ I scold. He chuckles. ‘I am too tired to shave and too busy to nap.’ I scrunch my nose while I consider his problem. ‘I know!’ I cry. ‘You nap and I will shave your whiskers. That will be two jobs tumbled into one!’ And so that’s what we do. Major Scruff slumps into a chair and snoozes while I lather his face with soapy water and shave his whiskers. The soap suds travel from his face, up into his hair and down the front of his uniform, and I have to shave his jaw and chin three times because I keep missing bits, but I finally get it all done. I am just wiping his cheeks dry when the dog appears. He licks my hand, then stretches up and licks soap suds from Major Scruff’s ear. Major Scruff wakes with a start. He feels his newly shaved face and cries, ‘Wonderful, Sasha! I feel smooth, clean, rested and ready for action.’ He ruffles my hair. ‘We must do this again tomorrow. Although next time, you might wake me with a gentle shake of the shoulder instead of licking my ear.’

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