Energy needed to connect two repulsive magnets

[bionic6manuel]

I have a problem that states how much energy would it take to make two repulsive magnets touch if the magnetic repulsive force is 51.7kg per magnet and the mass of magnet 0.515kg and the magnets are 2cm apart. This is the way I tried to solve the problem using the formula for work.

w= f * d
f= force
d= distance

Since I have two magnets the force between them will be 51.7kg*2kg= 103.4kg
weight of magnet 0.515kg * 9.8 m/s2 gravity = 5.047 Newtons

103.4kg * 5.047N * 0.02cm = 10.437 joulse. Is this true or should I have converted the magnetic repulsive force to Newtons.

 

[jbsteele]

Yes, you should have converted the magnetic repulsive force to Newtons first. The formula for work is w=F*d, where F is the force in Newtons and d is the distance in meters. Therefore, you need to convert the magnetic repulsive force of 51.7kg to Newtons first (1 kg = 9.8 Newtons). This would give you a force of 509.06 Newtons. Then, you can calculate the work as w=509.06N*0.02m = 10.1812 Joules.