Question

СРОЧНООО!!! ДАЮ 15 баллов!! На горизонтальних рейках, відстань між якими 50 см, у вертикальному однорідному магнітному полі з індукцією 0,5 Тл лежить перпендикулярно до рейок стержень масою 0,5 кг. Коефіцієнт тертя стержня по рейках 0,02. Який струм треба пропустити по стержню, щоб він почав рухатись?

Answer 1

To calculate the current required to start the movement of the rod, we can use the formula for the magnetic force on a current-carrying conductor:

F = BIL

Where: - F is the magnetic force - B is the magnetic field strength (induction) - I is the current flowing through the conductor - L is the length of the conductor

In this case, the magnetic force is equal to the force of friction acting on the rod. We can express the force of friction as:

F_friction = μ * m * g

Where: - F_friction is the force of friction - μ is the coefficient of friction - m is the mass of the rod - g is the acceleration due to gravity

Since the rod is at rest, the force of friction is equal to the magnetic force:

F_friction = F = BIL

Substituting the values given in the problem:

0.02 * 0.5 * 9.8 = 0.5 * I * 0.5 * 0.5

Simplifying the equation:

0.098 = 0.125 * I

Solving for I:

I = 0.098 / 0.125 ≈ 0.784 A

Therefore, a current of approximately 0.784 Amperes is required to start the movement of the rod.