H9 Paper

Semester 1

2012

ENB 130 H9 – Heat Production and Transfer

Tim Starkey n8588163

3rd of May 2012 10-12am Session Group Members: Daniel, Henry and Luke

Science and Engineering QUT

Aim Part A: Part B: To measure the heat output generated by an electrical current. To rank various materials in decreasing order of thermal conductivity so as to appreciate which materials are good and which are poor conductors. To examine the rate of cooling of a hot object.

Part C:

Introduction Energy is defined as an objects ability or capacity to do work [1]. Energy exsists as many different forms throughout the universe such as heat, sounds, kinetic, potential, chemical and many more. The law of Conservation of Energy states that energy cannot be created nor destroyed but instead only transformed from one energy type to another [2]. Heat is one form of energy related to the movement of atoms and molecules within an object. It is capable of being transferred through liquids, gases and solids by conduction, convection or radiation. Heat is transferred between objects as a result of temperature differences among them [3]. In part A of the experiment, the conversion of electrical energy into heat is observed through a convection transfer from a heating element in water. Electricity is a form of energy created by the flow of electrical charge or electrons through a conductor. Electrical power (P) is measured in Watts (W) and can be calculated for a circuit with the following formula: P=VI This formula only requires two knows to calculate an unknown in a conductor or circuit. If the voltage (V) and the current (I) are known, then the Electrical power can be calculated. Current, measured in coulombs per second, or ampere (A), is the rate that electrons pass through an electrical conductor or circuit. Voltage is an electrical difference between two points of a circuit. It measures the force required to pass one ampere through a resistance (R) of one ohm (Ω). Every...