magnetism / magnetic field and forces/ college-level physics please answer ASAP

Question

I have a question that asks to find the magnetic forces of the sides of a rectangular loop of wire in a region of a uniform magnetic field.

i know that the formula is F = I x L x B x sinθ and the angle is between the direction of the magnetic field and the direction of the current charging wire.

but i still don't know how to find the angle

this question needs a diagram to be understood so i provided a picture of the question in a dropbox sharing link :

https://www.dropbox.com/s/b58qcuej808fzo3/WhatsApp%20Image%202021-05-30%20at%205.01.01%20PM.jpeg?dl=0

please solve the magnetic force of ALL sides.

Answer 1

Here θ is angle between the length element and magnetic field which will be different for all sides.

Consider a constant magnetic field then angle between the opposite sides will be like

θ and 180-θ due to opposite direction of current.