Why does a kettle boil free essay sample

To do this investigation, I agree that I will follow all the risk control methods and conduct the experiment in a very safe condition. The aim of this investigation is to find out more about boil water by using a kettle. For example, time taken to boil different volumes of water, specific heat of water and power of kettle. Equipment: This picture shows all the equipment that I used to do the experiment including a stop watch, a measuring jug and an electric kettle with power between 1850w-2200w. Table 1: Time taken to boil five different volumes of water Volume (L) Time 1 (s) Time 2 (s) Time 3 (s) Average uncertainty time (s) in the average time (s) 0. 25 57 57. 5 58 57. 5 0. 5 0. 5 95 94 96 95 1 0. 75 132 135 134 133. 7 1 1 169 171 168 169. 3 1. 5 1. 25 209 211 212 210. 7 1. 5 To keep the data more accurate, I empty and cooling the kettle thoroughly before doing the next boiling. Diagram 1 Average Time taken to boil water 250 y = 152. 28x + 19. 03 Time (s) 200 150 100 50 0 0 0. 2 0. 4 0. 6 0. 8 1 1. 2 1. 4 Volume (L) As shown on the graph, there is a positive relation between time taken to boil water and the volume of water. We will write a custom essay sample on Why does a kettle boil or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page The equation for this line is y = 152. 28x + 19. 03. Therefore, the gradient of this line is 152. 28. As initial and final temperature are set at 25. 0o C and 100o C and the power of the kettle is 2025w (middle of the power range 1850w-2200w). Therefore, the heat of water can be calculated by using the equation: gradient = Where gradient is 152. 28, cw = the heat of water, ? T= change in temperature, P= power of the kettle. Therefore, cw = ?T = 152. 28? 2025 100o C? 25. 0o C = 308367 75 = 4111. 56J/kg  ° C, which means it costs 4111. 56J of energy to rise 1kg of water by 1 ° C Question 1 The reason why boiling water by using an electric kettle without elements are completely underwater is dangerous is that with water level above the element the maximum temperature will reach is 100o C. Otherwise, elements in the kettle will be overheated and burnt down as a result. Since the kettle transfers electrical energy to heat. Or more seriously, the whole circuit might be broken. Question 2 Different kettles may have different shapes and therefore the volume may not be set at a standard level. Instead, measuring jugs are produced under a standard level. Therefore, it would be more accurate to measure a specific volume of water. And as a result, time consumed to boil water would be more accurate with other elements are constant. Question 3 The reason why boil and empty the kettle before recording results is in order to make the kettle as empty as possible and cool the kettle down to the room temperature. Question 5 Cw (Specific heat of water) is the amount of heat per unit of mass needed to raise the temperature by one degree Celsius. Since the Cw that I calculated is 4111. 56J/kg  ° C which is close to the standard Cw which is 4200 J/kg  ° the Cw I measured was quite C, accurate. Question 6 In order to get a more accurate result, some measuring methods could be improved. For example, fill water at a completely accurate level, precise timing and cool the kettle down to the room temperature after each use of it.

Using the Spanish Noun Vez

Using the Spanish Noun Vez Vez (plural veces) is one of the most commonly used nouns of Spanish and can usually be precisely translated as occurrence, although in practice it is usually translated as time. Here are some examples of everyday usage: Mil veces te quiero, Alejandro. I love you a thousand times, Alejandro.Llegamos cuatro veces a la final. We made it four times to the final.Ser la à ºltima vez que me veas. It will be the last time you see me. Una vez is usually translated as once, although obviously it could also be translated literally as one time, and dos veces can be translated as twice or two times: Se toma una vez por dà ­a en un nivel de dosis decidido por el mà ©dico. It is taken once per day at a dosage level decided by the doctor. ¿Te has enamorado dos veces de la misma persona? Have you fallen in love with the same person twice?Sà ³lo se vive dos veces es la quinta entrega de la saga James Bond. You Only Live Twice is the fifth installment in the James Bond series. Veces can be used in making comparisons such as the following: Es una pila que dura hasta cuatro veces ms. Its a battery that lasts up to four times longer.La envidia es mil veces ms terrible que el hambre. Jealousy is a thousand times worse than hunger. Uses of Vez and Veces Vez and veces can be used in a variety of phrases. The following examples show some of the most common, although these arent the only translations possible: Alguna vez voy a ser libre. Sometime I am going to be free.El gato de Schrà ¶dinger sigue estando vivo y muerto a la vez pero en ramas diferentes del universo. Schrà ¶dingers cat was alive and dead at the same time but in different sections of the universe.A mi vez, no puedo comprender el tipo que dice que la casa es tarea de la mujer. For my part, I cant understand the type who says housework is a womans job. (Also used are phrases such as a tu vez, for your part, and a su vez, for his/her part.)Cada vez que te veo me gustas ms. Every time I see you I like you more.La actriz tolera cada vez menos la intrusià ³n en su vida. The actress is tolerating the intrusion in her life less and less.De vez en cuando es necesario perder la razà ³n. Once in a while it is necessary to be wrong.Estoy fantaseando en vez de estudiar. I am daydreaming instead of studying.A veces sueà ±o que ests conmigo. Sometimes I dream that you are with me.Los baratos muchas veces salen caros. Cheap things oft en sell for a high price.  ¿Por quà © el mar algunas veces se ve verde y otras veces azul? Why does the sea sometimes look green and other times blue?Habà ­a una vez una gata vivà ­a en una casita blanca. Once upon a time a cat lived in a little white house.Una vez ms Einstein tiene razà ³n. Once again, Einstein is right.La red otra vez fuera de là ­nea. The network went offline again.La felicidad se encuentra rara vez donde se busca. Happiness is rarely found where it is looked for.

The Justification, Planning, and Preparation for the Attacks by Al-Qai Essay

The Justification, Planning, and Preparation for the Attacks by Al-Qaida in the United States on September 11, 2001 - Essay Example This paper will seek to reflect on the detailed planning, preparation and attempts at justification that bin Laden and his entire Al-Qaida organization did prior to the devastating September 11th attacks. In my opinion, the United States had not afforded the proper degree of attention to the threat that was posed by the bin Laden led Al-Qaida organization. This is evidenced by although bin Laden is quoted in a report issued by the United Kingdom government as having issued a number of proclamations against the United States, urging Muslims around the world to kill both American citizens and their military forces, the United States never took any direct action against this potential threat. In making the threat, Osama bin Laden had justified the attacks by claiming that the people of Islam had for long endured suffering from the wanton injustice, aggression and iniquity that was being forcibly imposed on them by the Zionist-Crusader alliance and their respective collaborators. He argued that it was now time that Muslims engaged in a Jihad targeted at cleansing the land from these Arabian peninsula crusader occupiers. Of concern also is that even after the devastating attacks conducted by the group in East Africa, against United States targets, relatively very little effort was put in place to try reign in and cripple the threat that was being posed by this organization. According to the same United Kingdom report, Bin Laden had justified attacks on American and Jewish targets by claiming that Muslims that happened to die in the course of them would be rewarded as they were carrying out God’s work (Murphy 239). The planning for the attacks on the United States was very extensive and took a number of years as is seen to be characteristic of all the attacks conducted by the Al-Qaida organization. In moving the attackers to the United States several years prior to the attacks, taking them through flight schools and using flight simulators to help them carefully study the controls of some of the larger aircraft; I believe that the al-Qaida organization displayed a great degree of detail in its planning.  Ã‚