Final answer:
The average electrical power output is calculated by multiplying the current by the voltage, with a refrigerator in a dorm room example having 330 W output. Transmission losses are estimated based on resistance which is determined by cable material, gauge, and diameter, along with the length of transmission. Wired systems like those used by trains and buses are efficient as they avoid battery usage.
Step-by-step explanation:
Understanding Electrical Power Output and Transmission Losses
The average electrical power output of an appliance can be calculated by multiplying the current it draws by the voltage supplied to it. For example, a refrigerator that runs with a current of 3.00 A and a voltage of 110 V has an electrical power output of 330 W (3 A × 110 V). Additionally, if we add the power outputs of the lamp and overhead light which are 100 W and 60 W respectively, along with other devices totaling 3 W, the total power output for this student’s dorm room appliances is 493 W.
To estimate the percentage of power lost during transmission from the power plant to the dorm's appliances, we take into account factors such as the resistance of the transmission cables which is influenced by the material (aluminum), gauge (0-gauge), and diameter (8.252 mm) of the cables, as well as the distance (10 km). The resistance causes power loss, and the percentage can be calculated by using the power loss formula derived from Ohm's Law and factoring in the resistance over the length of the transmission path.
Trains and buses that run on electric power often utilize wired systems like overhead lines or a third rail to receive electricity, avoiding the issues of battery dependency and allowing for more efficient operation. High-speed trains tend to use this system due to the constant and reliable power supply that it offers.