A Hall probe consists of a strip of the metal bismuth that is 0.15 mm thick and 5.0 mm wide. Bismuth is a poor conductor with charge-carrier density 1.35 * 1025 m-3 . The Hall voltage on the probe is 2.5 mV when the current through it is 1.5 A. What is the strength of the magnetic field, and what is the electric field strength inside the bismuth?
History lecture 19 By the 1830 slavery had become a big national issue. The leaders of the country would handle the issue by ignoring it. In 18181819, Moses Austin was an American by birth but became a Spanish citizen. He recognized that America was about to take over Missouri, he moved to New Mexico. He got permission to settle land in Texas. Spain wanted to settle Texas because they saw how America was settling the west like crazy. They wanted to create a buffer zone between New Mexico and the rest of America to prevent the US from taking over their northern territory. When Austin went to talk to the Spanish government, he told them to let him sell land to Americans in Texas. The Mexican government said yes and gave him a license to sell land. But he ended up dying before he made it back to Missouri. His son, Stephen F. Austin, took over his fathers cause. He went back down to talk about protecting the land but this time with the Mexican Government, because by this time Mexico had become the Republic of Texas. He became an Empresario. He got so many acres of land for everyone he sold. When he saw the land, he saw the potential to make it the next great cotton kingdom. To make Texas a cotton kingdom they had to have land and slaves. The land was easy you had to become Mexican, catholic, ideally you had to learn to speak Spanish, be from a good family. After that the land was dirt cheap. Austin recruited most of his settlers from the southern states and they would bring their property with them. They would bring their slaves with them into Texas. This was the problem. Mexico had banned slavery in their new constitution. At first Mexico just look the other way when it came to slavery. By 1830 for every Mexican there was over 10 angloamericans living in Texas. When Americans comprise the majority, they tend to not take well when they are not in charge. When word got out how good the land was in Texas, people who were not with Empresario, would illegally invade Texas. Some of the small communities, had actually launched rebellion to over throw the Mexican Government so they could take over Texas. The Law of April 30,1829 made it illegal for Americans to settle in Texas. After that law was passed, a lot of the Americans who lived in Texas believed that they should have a role in Mexican Government because they were the majority. Austin was thrown in jail. By 1835, the Americans had began to form militias. They saw the Mexican government like they use to see the British. It got so bad that the Mexican Government sent their military to take away their guns. Word got out that one of the missions at Goliad had a cannon in it possession. The Mexican government sent the army to take it away. The people of Goliad had made a fort out of their community. When the army arrived the colonist set the cannon off killing the army. The first battle of the revolution occurred in 1835. The Battle of the Alamo in San Antonio soon followed. Sam Huston was the commander of the Texas Army. James Buoys and Travis were left in charge of the Alamo while the original commander of the Alamo went home to visit his family for Valentine’s Day and doesn’t return till March. Buoys and Travis got word that General Antonio Lopez de Santa Anna was marching to invade Texas and punish the settlers. A call for volunteers went out across Texas to defend the Alamo. 288 men showed up. By the end of February, Santa Anna showed up with an army of 2600 men and the battle began. Over the next 13 days the battle is fought. The Mexicans over ran the Alamo. It lasted for so long was because Satan Anna did not have the right cannons, Siege guns, and he couldn’t shoot through the wall. When the guns arrive, the Mexican army ran in, and they killed everyone including Davy Crocket. This became the inspiration that the Texans needed. It is because of this defeat that the Texans write their Declaration of Independence, March 6, 1836. 18 days later Sam Huston defeated Santa Anna at the Battle of San Jacinto. In this Battle, Huston forced Santa Anna to sign a peace treaty where they had to recognize everything North and East of the Rio Grande River as Texas. The Mexicans thought that the boarder of Texas began at the Nueces River and they thought that Texas was ¼ its side. The Treaty was never recognize by the Mexican Government because Santa Anna was under direst. As a result Texas Independence was never recognize by the Mexican Government. The was a coldwar between the two countries for the next 9 years. When Texas declared independence, the US was the first country to recognize this. The President of the US, Andrew Jackson, was good friends with Sam Huston the leader of the War Party in Texas. Mexico was convinced of US invoment that when Santa Anna signed the treaty that Mexico declared that if the US made any attempt to annex Texas that they would immediately declare war on the US. People did not want to bring Texas into the Union, mostly Northerners because of slavery. They did not want to bring such a big slave state into the union. 1836 1845Texas was a Republic because the US didn’t want to go to war with Mexico and there was so much opposition for the North. The early 1840’s, western expansion was kicked into high gear. Andrew Jackson destroyed the US economy because he would not renew the charter with the United States Bank because he thought they had too much power and the director was too powerful. Nicolas Biddle was the director of the bank, he said multiple time, “with the stroke of my pen, I could destroy the American Economy”. The bank moderated the economy. So when Jackson killed the bank who regulated the economy. Jackson put the federal deposits in banks controlled by democratic banks. Credit went wild. It was known as wild cat speculation. The banks would invest in the most risky businesses. Banks soon have more money out then they have in. There was so much credit that soon the banks called in the credit. There wasn’t enough money to call in all the credit. The panic of 1837 was an economic depression. Jackson made it worse when he issued the Gold Circular. It was an executive order that said that all the debts must be paid to the US government in gold coins only, no paper money. Back then for every 3 dollars bills there was suppose to be 1 dollar in gold coins. It because of this that people began to move west in the 1840’s so that they could go somewhere to make money. People wanted to move to Organ to began to tell the Indians about the Bible. Back then they would get on a boat in the east and for three months they would sail to the west. In 1841, a group of 80 men took the first wagon train across the Oregon Trail. They made Oregon out to be a farmers paradise. History Lecture 20 Quiz next Thursday of Geography Quiz. Study Guide on BlackBoard. Study guide for next exam will be posted on Friday The South Pass was what divided the east and west. It was the only pass that a wagon was able to through. A group of 80 men hired mountain men to teach them how to navigate the Oregon Trail. Oregon was made out to be the Land of Milk and Honey. Most settled by the Willemette River Valley. Every country had a claim on the Oregon Territory. The boundary was on the 42 degree line to the 53degree 40minute line. In 1827 Great Britten and the US signed the Joint Occupation Treaty. It legally recognized Oregon Territory as belonging to both the United State and Great Britain. The biggest issue was which country had the jurisdiction in the town. Neither country could extend its legal jurisdiction over Oregon. In that time the people out there were British and French fur trappers. In 1841 the British wanted the area north of the Columbia river and to the boarder of Canada. They wanted that area because of the fur animals there. So they had the colonist setting in the Wilemette River Valley where there wasn’t as many fur animals but good growing soil. Oregon represented a chance to find economic opportunity. By 1842 there was 160 families out in Oregon and it continued growing over the next years. By 1846 there was about 5000 US citizens. The Oregon Question was “Where would the US and Great Britain divide Oregon”. A couple years later after the Joint Occupation Treaty, the US wanted part of the Oregon land. They wanted to divide Oregon at the 49 parallel. The British had investments in that land. By the 1840’s the situation was changing. The election if 1844, both political parties were trying to figure out what to do about western expansion. The Democrats Party (created in 1832 by Andrew Jackson) ran Martin Van Buren from New York. The Whig Party (created in 1834 as an opposition party to Jackson Democrats) ran Henry Clay who was from Kentucky. Clay was not a fan of western expansion and said the Whigs were against western expansion. Van Buren was also against bringing in Texas. Van Buren was voted out and the Democrats went to James K. Polk from Tennessee to be their candidate. Polk was just like Jackson, Jackson was his ideal. Polk’s nickname was young hickory. He won the Democratic vote because he was for Texas. In his acceptance speech he said, “ReAnnex Texas and Reoccupy Oregon”. But Texas had never been annexed in the first place and Oregon had never really been occupied. In saying this he said that he was ready to go to war with Mexico and Britain. The American people elected Polk as president. His first priority was to settle the Oregon Question. He sent a letter to Britain and told them that he was pulling out of the Joint Occupation Treaty and told them that he was going to take all over Oregon. The motto was “54.40 or fight”. In 1845 Texas was a slave state in the Union and to counter that people wanted to bring Oregon in as a free state. In Oregon, the British had major fur trade with their main corporation on Vancouver Island. Eventually a treaty was send over where Britain said they would give them the 49 parallel but they wanted all of Vancouver Island. The US ratified it on June 6,1846. Polk had managed to avoid war with Great Britain. In 1844 President John Tyler, knowing that he was not going to be elected president, but he also knew that the people wanted Texas. He sent representatives to Mexico to work out a deal for Texas to join the union. Through a simple majority vote, Texas was asked to join the union. In December of 1845 Texas held a vote if they wanted to become part of the US. In march of 1845,mexico broke off diplomatic relations with the United State. Polk tried to make peace, he sent diplomats (who would eventually get kicked off Mexican soil) to meet with the Mexican Government. He offered to buy Texas, New Mexico, Arizona, and California. In late 1845, Polk sent an Army under General Zachary Taylor command to the mouth of the southern board to the mouth of the Nueces River (Near Corpus Christi). The reason was because that is where Mexico recognized the southern board of Texas. By being on the North side of Corpus Christi they could see if Mexican army was going to invade the US because they would have had to cross the Rio Grande River and walk 100miles of disputive territory. In November of 1845 nothing happened. In April of 1846, Polk ordered Taylor to march to the Rio Grande. It the Mexicans attack then the US is in defensive war, if Mexico doesn’t attack then it meant that the land was the United States. By early May of 1846, Polk wrote a Declaration of War against Mexico. The morning after he wrote it a cable arrived from General Taylor which told him that US soldiers were attack on the Northern side of the Rio Grande a few days before. This meant that it would be a defensive war. Polk ripped up his delectation of war and wrote a new one that said that American blood was spilled on American soldiers. This was one of the most unpopular wars in American History. It was supported by Southern but hated by Northern. The spot resolution was issued by Abraham Lincoln against Polk. He demanded that Polk bring a map and point to the exact spot that American Blood was spilt. Because he believed that the Slaveocracy had planned the whole thing. This was called the “spot Resolution”