In the uniform magnetic field with magnetic induction of 0.5T, there is an electrified wire AB which is perpendicular to the magnetic direction and 0.3m long. The current in the wire is 2a and the direction is a In the uniform magnetic field with magnetic induction of 0.5T, there is an electrified wire AB which is perpendicular to the magnetic direction and 0.3m long. The current in the wire is 2a and the direction is a to B. the magnitude and direction of Ampere force on the wire AB are calculated

In the uniform magnetic field with magnetic induction of 0.5T, there is an electrified wire AB which is perpendicular to the magnetic direction and 0.3m long. The current in the wire is 2a and the direction is a In the uniform magnetic field with magnetic induction of 0.5T, there is an electrified wire AB which is perpendicular to the magnetic direction and 0.3m long. The current in the wire is 2a and the direction is a to B. the magnitude and direction of Ampere force on the wire AB are calculated

The ampere force F = b * I * l = 0.5 * 2 * 0.3 = 0.3 n
The direction of Ampere force can be judged by left-hand rule
Stretch out your left hand and let the magnetic induction line penetrate into the palm of your hand vertically (direction B is not mentioned). Four fingers point to the direction of current (from a to b). The direction of thumb is the direction of Ampere force

There is a small section of conducting wire, 1cm in length, 5A in current intensity. Put it into a certain point in a certain magnetic field, and the magnetic field force is 0.1N. Find: the magnetic induction intensity B of the point must be ()
A. B = 2TB. B ≤ 2TC. B ≥ 2TD

The length is 1cm and the current intensity is 5A. When it is placed in a certain magnetic field, the magnetic force is 0.1N. When the magnetic field is placed vertically, the formula B = fil is: B = 2T. If the magnetic field is not placed vertically, the magnetic induction intensity is greater than 2T

A section of electrified wire is one centimeter long, and the current intensity is 5 A. when it is placed in a magnetic field, the magnetic force on a certain point is 0.1 N, and the current intensity B at that point must be greater than or equal to 2T
Please help me explain why it must be greater than or equal to 2T

F = bilcos θ, the critical condition is that when the direction of electric field is perpendicular to the direction of current and magnetic field, cos θ is taken as 1, and the force is the largest, otherwise 0 ≤ cos θ < 1. So when f is 0.1, I is 5, and l is 0.01, the conclusion can be obtained by simplifying the following formula!