A 150 kg person stands on a compression spring with spring constant 10000 n/m and nominal length of 0.50 what is the total length

The total length is 0.65m.

Explanation:

The total length of the spring is equal to its length right now (0.50 m ) plus the amount by which it is compressed due to weight of the man:

The spring compression is given by Hooke's law:

which in our case gives

solving for we get:

putting in and we get:

Hence, the total length of the spring is

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.