AP EVS Class 4
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01. LET'S GO TO SCHOOL EVERYDAY THINK AND WRITE 1. a) Steel, cement, bamboo, wood and bricks are the materials which are used to make a bridge. b) Yes, I did. That experience was good and I felt very safe because our workers work very hard to make this bridge safe for travelling. c) We need bridges to connect with villages, cities and other places where we can’t reach by roads because of the river, pond etc. d) Bamboo bridges are made by local villagers and cement bridges are made by engineers. The cement bridge can bear the weight of heavy vehicles like trucks, buses, etc. whereas a bamboo bridge cannot bear heavy weight. The durability of Bamboo Bridge is short whereas the durability of Cement Bridge is long. 2. (a) Typical materials used in making this bridge are steel, concrete, stone and asphalt. Other materials include iron, timber, aluminum, rubber and other joint materials. (b) Bridge is made across the river. (c) Yes, I have seen animals and vehicles crossing that bridge. (d) If there is no bridge over the river, people would have crossed the river by boat to reach their places. This would have consumed more time. 3. (a) Trolleys - A ropeway trolley is a form of naval lifting device used to transport light stores and equipment across rivers or ravines. It comprises a jackstay, slung between two sheers or gyns, one at either end, from which is suspended a block and tackle, that is free to travel along the rope and hauled back and forth by inhauls.. AP EVS-4 SOLUTION (GUJARAT BOARD) Page 1 (b) Bamboos - Bamboo is a typical plant from the grass family. Bamboo of its combined strength and light-weight, bamboo is one of the most used building materials for making houses, bridges, furniture, etc. It is used as fuel. Bamboo pulp can be used to make paper. (c) Wooden Boats -The hull of a wooden boat usually consists of planking fastened to frames and a keel. Keel and frames are traditionally made of hardwoods such as oak while planking can be oak but is more often softwood such as pine, larch or cedar. (d) Cart -Cart is especially used for carrying goods and people from one place to another. It is pulled by one or several oxen. It is attached to an ox team by a special chain attached to yokes, but a rope may also be used for one or two animals. The driver and any other passengers sit on the front of the cart, while load is placed in the back. 4. I. - b ii. - d iii. - a iv. – c LET’S DO IT What You Need: 2 Solar cells 2-4 Alligator clip leads Rubber bands AP EVS-4 SOLUTION (GUJARAT BOARD) Page 2 Small electric motor (Look at hobby or electronics stores, and make sure you get one with a motor pulley) For the car body: cardboard milk carton, water bottle, cardboard, foam board, or similar materials For the wheels: plastic bottle caps, film canister caps, toy wheels such as K'nex, etc. For the axles: Stiff wire or wooden shish-kabob skewers Straws or eye screws to mount the axles What You Do: 1. Choose a material for the car body, which is called the chassis. Think carefully about this: you want something strong, but also something lightweight so it needs less power for the motor to move it. (But be careful — if it's too light, it can easily get blown about by the wind.) A big part of engineering is finding the right balance between weight and strength. 2. Use a nail to poke a small hole in the center of your wheels. Make sure the stiff wire or wooden skewers you use for axles fit in the holes tightly. Take an extra cap and cut off the sides, leaving just the top part, which usually has a small inner rim to help keep the bottle from leaking. Glue this cap to one of your wheels. You have just created a pulley for your driving wheel; the inner rim of the extra bottle cap will support your car's drive belt. (You can try using a film canister cap for this step instead of cutting a bottle cap. If you are using toy wheels like K'nex, you can just use a smaller wheel mounted on the inside of your main wheel to act as the pulley.) 3. Now, mount your axles onto the chassis. Depending on what your chassis is made of, you can thread the axle through eye screws mounted on the bottom. Another easy method is to tape straws on the underside of thechassis and thread the axles through them. 4. Attach the small motor pulley to the motor shaft. Determine where to mount the motor by connecting the driving pulley with the motor pulley using an elastic band as a drive belt. Position the motor so the band is AP EVS-4 SOLUTION (GUJARAT BOARD) Page 3 slightly stretched (but don't stretch it too much!). Mount the motor with glue or tape it in between a small frame of wood or cardboard blocks. 5. Use clear plastic tape to attach the two solar cells together side-by-side; then connect them in a series circuit using the alligator clip leads. Connect the positive terminal of one cell to the negative terminal of the other. Connect the remaining terminals to the motor. If the motor spins the wrong way, switch the leads where they connect to the motor. Once it's connectedproperly, you'll probably want to use to tape to help keep the wires under control. 6. Mount the solar cells on the chassis at an angle where they will receive the most sun. Take your car outside to a sunny sidewalk, connect the drive belt, and watch it go! 02 - EAR TO EAR i. (d) ii. (a) iii. (b) iv. (f) v. (e) vi. (c) 2. Animals whose ears can be seen Deer Cat AP EVS-4 SOLUTION (GUJARAT BOARD) Page 4 Giraffe Pig Elephant Cow Buffalo Tiger Animals whose ears cannot be seen Snake Ant Lizard Sparrow Duck Frog Fish 3. a) Do it yourself b) Snake and Sparrow c) Birds hear with the tiny holes. d) Animals need ears because without ears they cannot hear the sound of predators so that they can escape and prevent themselves from them etc. AP EVS-4 SOLUTION (GUJARAT BOARD) Page 5 e) Animals have different patterns on their body because every animal has different skin and hair which makes them different from each other. 4. a) Yes b) No c) No d) Yes e) No 5. a) Tiger b) Zebra c) Snake d) Fox e) Giraffe f) Crocodile g) Deer h) Squirrel 6. Name of Ears can be Has Hair on Has Feather the seen Skin on skin animals a. Frog b. Fish c. Deer d. Crow e. Mouse f. Hen g. Buffalo AP EVS-4 SOLUTION (GUJARAT BOARD) Page 6 h. Duck i. Peacock j. Sparrow 7. a) Lioness , Tigress b) Hen , Duck c) Deer, Tiger d) Cow, Horse e) Pigeon ,Crow f) Birds, Hen LET’S DO IT PROCESSES OF MAKING A PAPER PEACOCK. 1. Take a sheet of dark green paper and make one fold up, about two centimeters wide. 2. Turn the paper over to the other side, and make another fold in the same way. 3. Continue turning the paper over and making folds until you reach the end of the paper. You should have an accordion-like pleat of folds. 4. Cut the paper in half along one of the folds. Fold one half of the paper in half, along the width. Repeat with the other half. Take the inner ends of one half of the paper, and glue them together. Do the same with the other half. You should have two pleated semicircles. 5. Staple the semicircles together to make one full circle. Now you have made a circular fan. 6. Paint small red, yellow and blue dots on your circular fan. Wait for the paint to dry. Glue the sequins on top of the dots of paint for some added sparkle.Cut out a peacock body shape from the blue cardstock. 7. Paint the peacock's body all over with the blue glitter glue. Wait for it to dry. Glue the googly eye onto the peacock's body.Cut out a small triangle from the AP EVS-4 SOLUTION (GUJARAT BOARD) Page 7 yellow cardstock, and glue it onto the peacock's body. This is the peacock's beak. Glue the green feathers onto the peacock's body. These are its wings. Glue the popsicle stick between a fold on the circular fan. Glue the peacock's body onto the popsicle stick. ACTIVITY TIME Bengal Tiger— It is threatened by poaching, loss, and fragmentation of habitat. Asiatic Lion— have died since January for various reasons such as snake bite, drowning, natural death, infighting and disease Babesiosis. Blackbuck—Poaching, habitat destruction, habitat fragmentation, urbanisation and neglect are the major causes for the disappearance of Blackbuck. Red panda— It is primarily threatened by habitat loss, fragmentation, poaching, and illegal pet trade. One horn rhino—Initially, numbers dropped due to hunting, but today the main threats to rhino are poaching and habitat loss. 03 - A DAY WITH NANDU THINK AND WRITE a) Some animals move in groups because living in groups helps them to avoid getting eaten by predators and working together can also help them find more food. b) A group of elephants is called a herd.