To understand the effect of decreasing current on the force experienced by a conductor, we need to consider the relationship between the force and current. The force [tex]\( F \)[/tex] experienced by a conductor in a magnetic field is given by the formula:
[tex]\[ F = BIL \sin(\theta) \][/tex]
In this formula:
- [tex]\( F \)[/tex] is the force
- [tex]\( B \)[/tex] is the magnetic field strength
- [tex]\( I \)[/tex] is the current
- [tex]\( L \)[/tex] is the length of the conductor
- [tex]\( \theta \)[/tex] is the angle between the magnetic field and the direction of the current
Given that the direction of the current does not change, the angle [tex]\( \theta \)[/tex] and the values of [tex]\( B \)[/tex] and [tex]\( L \)[/tex] remain constant. Therefore, we focus on the relationship between [tex]\( F \)[/tex] and [tex]\( I \)[/tex].
If the amount of current [tex]\( I \)[/tex] decreases while all other factors [tex]\( B \)[/tex], [tex]\( L \)[/tex], and [tex]\( \theta \)[/tex] remain unchanged, the product [tex]\( BIL \sin(\theta) \)[/tex] also decreases. Hence, the force [tex]\( F \)[/tex] experienced by the conductor will decrease.
Therefore, the correct answer is:
B. becomes weaker