ofia investigates how the current in an electromagnet affects the strength of the electromagnet.a State two variables that Sofia must keep constant during this investigation

Sofia investigates how the current in an electromagnet affects the strength of the electromagnet. a State two variables that Sofia must keep constant during this investigation. [1] 1. _____________________________________________________________________________ 2. ____________________________________________________________________________

Analyze the factors that affect the strength of an electromagnet.

How does the number of turns affect the strength of the electromagnet?a.Directlyb.Indirectlyc.Independent

The figure shows a simple electromagnet made of a coil of insulated wire wrapped around an iron nail.When the switch closed, which of the following will make this electromagnet stronger? (i) increasing the number of coils(ii) adding more turns to the coil(iii) increasing the direct current flowing through the coil(iv) changing the direct current flowing through the coil to alternating current.*1 pointii, iiii, ii, iiiii onlyiii only

The magnetic effect of electric current was first observed by __________