explain how an earth wire in an appliance can help to prevent damage or injury to users when a fault occurs in the appliance.

Simply put: the grounding wire is a way of electrical protection. Its function is to quickly connect the current to the earth through the grounding wire when your electrical equipment is leaking or inductively charged, so that the equipment shell is no longer charged, thereby ensuring the safety of the equipment behind the personnel.

Explanation:

For example, due to poor insulation performance of household appliances or humid environment, the shell will be charged with static electricity, and electric shock accidents may occur in serious cases. In order to avoid accidents, a wire can be connected to the metal shell of the electrical appliance, and the other end of the wire can be connected to the ground. Once the electrical leakage occurs, the grounding wire will bring static electricity into the ground and release it. In addition, it is more important for electrical maintenance personnel to use electric soldering irons to solder circuits, sometimes because the electric soldering irons are charged and break down and damage the integrated circuits in the electrical appliances. Friends who use computers sometimes ignore the grounding of the mainframe. In fact, connecting a ground wire to the mainframe of the computer can prevent the occurrence of crashes to a certain extent.

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the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

your answer is, orbit around the nucleus