A 200 tonne train experience wind resistance equivalent to 60 erating efficiency of the driving motors is 0.87 and the cost of el kWh. What is the cost of the energy required to make the train min is supplied at a constant voltage of 1.5 kV and travels with a mat is the supply current?

Q A Solar water heating System connected to 250 kg water- energy storage tank has UA equal 12 2 and is located in aroom that is at a constant temperature 20c where the load is 20 MJ, the final temp storage tank is not exceeding to 98e, the intial temp. is use Find the required energy delivered to storage tank take ( st=1) 2. Calculate the number of collectors if the efficiency of the collector is yo% the dimensions of the Collector is (100 cm * 75cm) and the total globle radiation is 6.6 Kwh/m² .

A wind generator rotates at 17 rpm on the rotor (the part with the blades). It is a direct drive (meaning the rotor connects directly to the generator). The generator is 86% efficient and produces 3.1 MW. What is the torque on the rotor?

A tank of water has a shaft rotating at 60 rpm with a torque of 40 N-m that is stirring the water. A heater is also present that operates at 120V and draws 4A of current. Heat is then removed from the water such the total energy content of the water is constant. How much heat is removed?