Sound waves are mechanical waves. They can travel only through matter. They cannot travel through empty space. This was demonstrated in the 1600s by a scientist named Robert Boyle. Boyle placed a ticking clock in a sealed glass jar. The clock could be heard ticking through the air and glass of the jar. Then Boyle pumped the air out of the jar. The clock was still running, but the ticking could not be heard. Thats because the sound couldnt travel without air particles to transfer the sound energy. Is there any other place where sound cannot be heard? Here is a hint: is there any other place that does not have air molecules? Thats right, in space sound cannot be transferred. So can astronauts hear each other? Yes, they can, because they are in enclosed space stations or pressurized suits.In both cases, they are surrounded by air molecules. If they left their space ship and did not use their electronics, they would not be able to hear each other. Next time you watch a science fiction movie, think about this factoid. When spaceships are destroyed by hostile alien beings, there would be no sound heard. Sound waves can travel through many kinds of matter.

Question: "How did Robert Boyle prove the properties of sound waves?"

Response: "With a clock in a jar of water, and there was no sound."

A: no

Have you are burned something on the stove or in the oven? Do you know why things burn? It all has to do with temperature. Changes in matter are affected by temperature. For example, what if you place a cake in the oven and you leave it in too long? What do you think will happen? Thats right, it will probably burn. The same thing will happen if the oven setting is too high and you apply too much heat. In either case, heat has affected the rate of change in matter. Its probably obvious that when the temperature is increased a chemical change, like cooking, will occur faster. What about a physical change? Are physical changes affected by temperature? Most of us have seen steam rising off a wet road after a summer rainstorm. This happens because the road surface is very warm. The warm road and warm air temperature causes the water to evaporate quickly. The liquid water is turning into water vapor, but it is still water. The evaporation of water is a physical change. So yes, temperature affects the rate that physical change occurs.

Question: "What kind of changes can be caused by temperature?"

Response: "Evalporation"

A: no

The movie is a powerful story that deals with feminism and patriarchy in the middle class of India . It is shot in the present and past tense showing lives of the characters Mahender and Sudha as they lived together as well as separately . The movie starts with Mahender getting down at the railway station and making his way to the waiting room just as it starts to rain heavily . A woman , Sudha , is already sitting in the waiting room . On seeing him , she tries to hide her face from him but later they confront each other . Mahender has an accomplished business dealing with photography . He respects his grandfather immensely . Incidentally , he had been engaged to Sudha for 5 years but always made some excuse to delay their wedding . However , this time his grandfather has fixed the wedding on the first week of the following month . He reveals to Sudha that he is having an affair with one of the most radical representations of feminism in a girl called Maya . He returns to tell Maya , but Maya has disappeared , leaving him some poetry . Mahender then marries Sudha and is quite happy , but the sudden return of Maya causes tensions in their married life . Mahender frequently tells Sudha about all the beautifully poignant , loving and authentic things Maya did over the years that they lived together . Later , Maya tries to commit suicide , and this leads to Mahender spending time with her over a few weeks . Sudha , not knowing about Maya 's suicide attempt and therefore believing that Mahender is being unfaithful to her , feels that her marriage was a mistake , and questions Mahender about his intentions .

Question: "What pushed Mahender to spend time away from Sudha?"

Response: "His grandfather's photography shop"

A:
no