A magnifying glass has a convex or converging lens. When a parallel beam of light passes through the lens, the light is brought to a focus point. Light that enter the lens at a single point are sufficient to raise the temperature and the temperature is high enough for a chemical reaction to occur.
To lit up the match stick, hold your magnifying glass at a comfortable direction and slighty 0.5m - 1.0m away from the match stick. Try adjusting the glass to redirect the sunlight and focus it directly on the black head of the match stick. Try not to move your hands and if you are lucky enough, with the strong sunlight, within a minute you can lit up your match stick!
1) How many images would you get for an object that is placed between two mirrors placed at an angle less than 90(degrees)?
For an image place at an angle of 90 degrees, 3 images are produced. For an image place at an angle lesser than 90 degrees, more than 3 images are produced. For example, at 60 degrees, 5 images are produced. At 45 degrees, 7 images are produced.
2) What happens to the images if the angle is bigger than 90(degrees)?
The images produced will have different views. For example, if two mirrors are placed at 120 degrees, 2 images are produced. Which mean, the greater the angles, the lesser the images are formed.
3) How do mirrors produce funny images?
Through different shapes of mirrors. Different shapes of mirrors have different geometrical properties. If you stand in front of a concave mirror, the image produced will be stretched and shows a fat image of you. If you stand in front of a convex mirror, the image produced is thinner and shows a slimmer and taller image of you.
Microwaved food is believed to contain microwaves.
I don’t think so. Firstly all food contains water molecules (H2O). The microwave (electromagnetic wave) is passing through the food. This is only making the water molecules (H2O) in the food vibrate. This process produces friction which is then transform into heat energy and heat up the food in the oven.
How safe is microwaved food?
There are some dangers in microwave food. For example, nutritional dangers, electromagnetic dangers, toxic dangers, chemical dangers, and many more.
In nutritional dangers, the nutritional values in food is reduced. As microwave cooked foods lose water, they will lose many vital nutrients and minerals. This will cause deficiency diseases, because consumers are not able to take in the sufficient amount of essential nutrients needed daily. This especially applies to the preparation of the milk, fed to the infants. If their milk is prepared by microwave cooking, the nutrients in the milk are most likely to be lost, and infants mostly only have milk as their only source of food, so it is not recommended. Therefore, this nutritional danger contributes to the danger of microwaved food.
There are also electromagnetic dangers. Microwaved food are likely to lower electrochemical activity in the brain. Often exposure to the radiations in microwaves can result in headaches, backaches, disorientation and altered brain wave patterns. These were all scientifically proven. Therefore, it will contribute to the danger of microwaved food.
Nonetheless, toxic and chemical dangers. When food is microwaved in a plastic container, toxins may leech out to the food during cooking, and is potentially harmful for consumers. When food is heated by the microwave, there are chemical alterations present in the food. Excessive consumption of microwaved foods can lead to a decrease in haemoglobin in the blood, decrease in beneficial cholesterol and decrease numbers of disease-fighting white blood cells. As a result, these can lead to anemia, lowered immune responses, and a greater risk of heart disease. Therefore, it is a threat to the safety of consuming microwaved foods.
Hence, microwaved foods are not very safe, because there are too many harmful risks to the human body. But, there is also advantage. Microwaved foods will help to kill harmful materials and make foods easier to digest.
Question: What would be the effect if a spaceship landed, and the aliens in it estimate that they are 400 years ahead of us. What would happen if they offered us all their scientific knowledge? Would it be good or bad? Why?
It would be good. With their scientific knowledge, i think we, human beings, will be able to live in a better environment. When they shared their scientific knowledge with scientists around the world, scientists will be able to turn a impossible task into a possible one. New inventions and discoveries will be made and discovered. Scientist will also lessen their testing and trial and error through experiment and inventions.
Since Science is consist of three main schools - Biology, Physics and Chemistry. I will explain this into three parts.
For example, in Chemistry. Doctors and scientists will be able develop new treatments for medical conditions and symptoms in a shorter way through Alien. This will help to cure deadly diseases such Aids, Colon Cancer, etc. With this, there will be more hope for the cancer patient. Also, Scientists will be able to create new drugs that are stronger and cure sickness at a faster rate.
In Biology. Through biology we can study deeper and grow our knowledge on the human body and further our medical understanding. This will save millions of lives worldwide.
In Physics. We will be able to deepen the laws of physics. This is very important, especially engineer. It will help them to construct building block to many other applications. It is fundamental to communication systems, the automotive industry, power generation, space exploration, etc. Through Alien, perhaps, it will help engineers to construct many new things that are more stable and benefit us. This will eventually help to develop our world into a highest technology level and turn our world into a better urban environment.
Last but not least, through their knowledge, we are not just gaining something new but also develop friendship with them as well. Also enabled us to develop socially and better ourselves. With that, we will be able to learn something from them. Through friendship, we will also be able to find out more on their planet, their characteristic and habitats.
In my conclusion, this is definitely a golden opportunity for us to deepen our knowledge for science. It is definitely a good thing. If we are going to continue to develop, we must search for a better and more meaningful life and science is the best vehicle to achieve this object. But through the alien's scientific knowledge we will able to achieve our goals in a fastest time and in a shorter way. I believe their scientific knowledge will definitely provides us with a more logical, more factual and more generally rational explanation of the world around us!
Fans create air flows with high volume and low pressure. The blade will rotate when exposed to an air stream. Fans work by moving the air that is in the area of the fans. This movement of air will create a breeze. But this breeze itself does not actually feel cool. It is a cooling effect from the fan's air that helps. This air will help to evaporate our sweat faster, thus cooling our skin. The fan contains a motor which is run by electric current that is connected to fan blades by a shaft. This rotor shaft is operated by the motor and able to turn the blades in different speeds. This speed is depending on the speed set for the motor. When the electric current activates the motor, the rotor shaft spin, in turn moving the blades through the air. The inclination of the fan blades force all the airthat hits their front surface forward. This create a continous movement of the moving stream of air. For your information, the fan does NOT change the temperature of the air! In older days without air-conditioner, fan is the only household appliance that keep us cool. Although fans take up more spaces compare to air-conditioner that are place on the wall, but it uses less electricity. The creation of the fan is not just amazing but also contributes to the comfort of people.
