- #1

Student149

- 58

- 0

Thread moved from the technical forums to the schoolwork forums

Consider 2 similar solenoids/electromagnets with appropriate iron core with the following parameters: core Length (

Let the two electromagnets initially be held together end to end by some physical force inside a hollow glass tube horizontally, such that 2 north poles touch each other i.e. the distance b/w them is 0. Initially the current is 0. Now the current is switched on and when it reaches (

We are assuming the hollow tube they are held in offers 0 friction or resistance when they travel away from each other. Moreover, we are ignoring all other external factors like air resistance, and gravity etc.

**L**), core Radius (**R**), electromagnet wire diameter (**w**), number of turns of wire/winding layer on the core (**L/w**), number of layers of winding (**K**), total number of turns (**(L*K)/w**), final current (**I**), mass of each electromagnet (**m**).__Case 1:__Let the two electromagnets initially be held together end to end by some physical force inside a hollow glass tube horizontally, such that 2 north poles touch each other i.e. the distance b/w them is 0. Initially the current is 0. Now the current is switched on and when it reaches (

**I**), the mechanical force holding together the electromagnets is released.We are assuming the hollow tube they are held in offers 0 friction or resistance when they travel away from each other. Moreover, we are ignoring all other external factors like air resistance, and gravity etc.

**Query 1:**What is the formula to calculate much time (**t0**) would it take for the two electromagnets to reach a distance (**d0**) from each other when the mechanical force holding them together is released?**Query 2:**What is the formula for force b/w the two magnets using the above parameters w.r.t the distance (**d**) or time (**t**)?**Instead of being horizontal the tube is now vertical and one of the electromagnets is pressing against the ground so only the top magnet can move. With the same initial setup, instead of distance we want to calculate the height (**__Case 2:__**h**) :**Query 1:**What is the formula to calculate much time (**t0**) would it take for the top electromagnet to reach a height (h**0**) from bottom magnet's north pole, when the mechanical force holding them together is released?**Query 2:**What is the formula for force b/w the two magnets using the above parameters w.r.t the distance (**h**) or time (**t**)?This is not some h/w Q but I am personally revisiting electromagnetism and looking for a blackbox formula. I have forgotten much of it so due apologies beforehand.