Magnets are able to place a force on certain materials. This force is called a magnetic force. The force a magnet exerts is a little different from the forces you may normally think about. You exert a force on a book when you lift it. You also exert a force on the pedals of your bicycle. In both those cases, those forces cause a change. The change you see in both these cases is called motion. Magnets, too, can produce change. They can produce motion just like you do. Unlike you, magnets do not have to touch something to exert a force. A magnetic force is exerted over a distance. Thats right, a magnet can push or pull certain items without ever touching them. Thats how the maglev train works. Do you know another type of force that does not require objects to touch? These forces are known as non-contact forces. Another type of non-contact force you may be familiar with is gravity. Gravity too can cause changes in motion. Gravity holds our moon in orbit without touching it.

Question: "How are magnetic forces different from other forces?"

Answer: "Other forces cause a change called motion"

Response: no

The 1933 double eagle, a $20 gold piece with a mysterious history that involves a president, a king and a Secret Service sting operation, was auctioned Tuesday last night for a record price for a coin, $7.59 million, nearly double the previous record. The anonymous buyer, believed to be an individual collector who lives in the United States, made the winning bid in a fiercely contested nine-minute auction at Sotheby's in Manhattan. Eight bidders were joined by 500 coin collectors and dealers in an auction house audience seemingly devoid of celebrity bidders, while an additional 534 observers followed the bidding on eBay. As auction houses prepare for their fall seasons in an uncertain economy, the sale price "suggests that the marketplace for important items is enormously strong," said David Redden, a vice chairman at Sotheby's, who was the auctioneer. "This is an astonishing new record for a coin," he said. In an unprecedented move, the auction proceeds were split by the U.S. Mint and a London coin dealer, Stephen Fenton, who had won that right in court after having been arrested by Secret Service agents for trying to sell the coin in the Waldorf-Astoria Hotel in Manhattan in 1996. Henrietta Holsman Fore, the director of the U.S. Mint, who witnessed the sale, said, "The monies we receive will go toward helping to pay down the debt and to fight the war on terrorism." Fenton commented that the double eagle had been on "a long historic journey, with a very satisfying ending." He added, "I am thrilled with the price." The previous numismatic record holder was an 1804 U.S. silver dollar, which sold for $4.14 million in 1999. Sotheby's partner in the one-lot auction was Stack's Rare Coins, with which it shared the customary 15 percent commission. "I have never seen as much interest in the sale of any coin in my 30 years in the business," said Lawrence R. Stack, the company's managing director. "This is the Mona Lisa of coins," said Beth Deisher, editor of Coin World, the largest weekly coin publication in the United States, with a circulation of 85,000. "It is unique. Forbidden fruit." Collectors' Web sites have surged with speculation about the sale price, and enthusiasts even organized betting pools.

Question: "Where did the person live that bid and won the $20 double eagle gold piece?"

Answer: "Germany"

Response: no

Earths magnetic field helps protect Earth and its organisms. It protects us from harmful particles given off by the sun. Most of the particles are attracted to the north and south magnetic poles. This is where Earths magnetic field is strongest. This is also where relatively few organisms live. Another benefit of Earths magnetic field is its use for navigation. People use compasses to detect Earths magnetic north pole. Knowing this helps them tell direction. Many animals have natural 'compasses' that work just as well. Birds like the garden warbler in Figure 1.36 use Earths magnetic field. They use it to guide their annual migrations. Recent research suggests that warblers and other migrating birds have structures in their eyes. These structures let them see Earths magnetic field as a visual pattern.

Question: "Where is the structure located, that warblers use to detect the magnetic fields of Earth?"

Answer: "Garden"

Response: no

Dick was enraged to see how contentedly the men bore the irksome confinement, the meager food, and harsh peremptoriness of the beardless boys set over them as guards. Most of the prisoners passed the time in cards, playing for buttons, trinkets, or what not that formed their scanty possessions. Dick learned that all the commissioned officers of the company with Wesley Boone had been wounded or killed in the charge near the stone bridge. Wesley had been with the prisoners at first. He had been struck on the head, and was in a raging fever when his father and sister came to the prison to take him away. No one could tell where he was now, but Dick knew that he must be in the city, since there were no exchanges, the Confederates allowing no one to leave the lines except women with the dead, or those who came from the North on special permits. Then he visited the provost headquarters, and was shown the complete list of names recorded in the books there; but Barney's was not among them. At the Spottswood Hotel, the day after his coming, he met Elisha Boone, haggard, depressed, almost despairing. Dick had no love for the hard-headed plutocrat, but he couldn't resist making himself known.

Question: "Who met with Elisha Boone at the Spottswood Hotel?"

Answer: "Wesley"

Response:
no