Calculate the magnetic field at the centre of a current carrying loop which is in the form of square of sides 4 cm and carries a current of 5 ampere ​

Which statement correctly describes a step-up transformer? a. it increases the amount of electric energy available. b. it increases the voltage of an electric current. c. it changes direct current into alternating current. d. it has more loops of wire in its primary coil.

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?

What are two different ways you could find the value of a? explain these methods.