when an electric current is 32A (amperes), the electromotive force is 288 V (volts).?

Question

Find the force when the current is 65A if the force varies directly as the current.

Answer 1

First find the resistance of the load.
R=E/I or 288/32=9 Ohms
E=IR or E=65*9 or 585 Volts.

Or Varies directly - set up a ratio:
288/32=E/65
9=E/65 or E=585

Either way is fine. Which ever is easiest for you.

Answer 2

Current and "force" do not vary directly. 5 volts could just as easily produce 32 amps, as 480 volts, or any other voltage for that matter. Are you stating that the first voltage in your question is 288 volts, or are you asking if it is? If stating that the emf is 288, then the circuit resistance is 9 ohms. "If" is a variable, what "if" the voltage does not vary directly with the voltage? Your circuit resistance could drop, and the current rise to 65 amps, with an emf applied of 288 volts.