Because of low temperature the water inside the bottle freezes. On freezing it expands, thereby its volume increases and pressure is exerted on the walls.
Dinosaurs probably communicated both vocally and visually. Large meat eaters like Tyrannosaurus rex, with its loud roar, or a Triceratops shaking his head, would have made its intentions very clear. The chambered head crests on some dinosaurs such as Corythosaurus and Parasaurolophus might have been used to amplify grunts or bellows. Mating and courtship behavior and territory fights probably involved both vocal and visual communication. Scientists believe that the sounds created by dinosaurs like Parasaurolophus were so individual that each had a slightly different tone. They also believe that these dinosaurs had different calls, ranging from low rumbles to high-pitched notes, which they used for different situations.
Scientists do not know for sure why dinosaurs became extinct. They have many different theories, some of which explain the extinction as something that happened gradually over a long period of time. Other theories suggest that a single catastrophe, such as fallen asteroid from outer space, caused the dinosaur population to die off rather suddenly. And some scientists believe the dinosaur population had been gradually getting smaller and then was finished off by some dramatic event. Those who believe gradual changes brought about the dinosaurs’ end suggest that, as more and more mammals appeared, the dinosaurs had trouble competing with them for food sources. And these mammals may have eaten dinosaur eggs in such large numbers that fewer and fewer baby dinosaurs were born. Some experts believe that widespread disease killed off dinosaurs. Many suggest that gradual climate changes—from continuously warm, mild weather to seasonal variations with hot summers and cold winters—affected the dinosaurs. Scientists are not sure whether dinosaurs were warm-blooded or cold-blooded (and there may have been some of each). If they were cold-blooded, meaning that their body temperature changed depending on the temperature of their surroundings, it would have been difficult for such large animals to survive extreme temperatures. Smaller coldblooded creatures can burrow under the ground, for example, to escape both heat and cold. But most dinosaurs were simply too large to do that. The scientists who believe that dinosaurs became extinct after a major catastrophe point to evidence that suggests a huge asteroid, perhaps several miles wide, hit Earth. The impact of such an object would have created enormous clouds of dust and other debris. The heat of impact would have started fires over a great area. Between the dust clouds and the smoke from the fires, sunlight would have been blocked, maybe for several months. A lack of sunlight would have caused a dramatic drop in temperature, and much plant life would have died. Without plants, the plant-eating dinosaurs and many other animals would have died; without the planteating dinosaurs and those other animals, the meat-eating dinosaurs would eventually die as well.
The federal government is the national government of the United States of America. It includes the executive, legislative, and judicial branches. The executive branch is responsible for enforcing the laws of the United States. Its main components include the president, the vice president, government departments, and independent agencies. The president is the leader of the country and commander in chief of the armed forces; the vice president is the president of the Senate and the first in line for the presidency should the president be unable to serve; the departments and their heads (called Cabinet members) advise the president on decisions that affect the country; and independent agencies help carry out the president’s policies and provide special services. The legislative branch is the lawmaking branch of the federal government. It is made up of a bicameral (or two-chamber) Congress: the Senate and the House of Representatives. The judicial branch, made up of the Supreme Court and other federal courts, is responsible for interpreting the meaning of laws, how they are applied, and whether or not they violate the Constitution.
Mahendra Singh Dhoni. Dhoni ties knot with longtime friend Sakshi on Sunday July 4, 2010 in a private ceremony attended only by family members and close friends, including a few of his team-mates at Dehradun.
The Etruscans of ancient Italy ritually honoured their dead war heroes by sacrificing the lives of all prisoners seized in battle. After conquering the Etruscans, the Romans borrowed and embellished the ritual by having the prisoners kill each other. They turned the slaughter into public gladiatorial games and declared the spectacle a Roman holiday, which became an expression synonymous with any cruel and crushing public destruction.
During the Second World War, Native American paratroopers began the custom of shouting the name of the great Indian chief Geronimo when jumping from a plane because, according to legend, When cornered at a cliff’s edge by U.S. cavalrymen, Geronimo, in defiance, screamed his own name as he leaped to certain death, only to escape both injury and the bluecoats.
In Irish folklore, a supreme con man named Jack, or “Jack-o,” once tricked the Devil himself. Upon his death, his sins barred him from heaven, and because he had once fooled the Devil he couldn’t enter hell. After a lot of begging he finally persuaded Satan to give him one burning ember. Placed in a hollowed-out turnip it served as a lantern to light his way through the afterlife. Later in North America, the plentiful pumpkin replaced turnips for use as “Jack-o’s lanterns.”
The magnetic needles of a compass under the influence f the earth?s magnetic field lie in a north-south direction. Hence, we can identify direction.