2/A mains electricity hairdryer has a resistance of 46 Ω and a current of 5 A flows through it when in use. What is the voltage across the hairdryer? (This is the mains voltage in the UK) 3/ What is the voltage across a lamp of resistance 4 Ω if a current of 2.5 A flows through it?

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Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.