Atypical garden hose has an inner diameter of 5/8". let's say you connect it to a faucet and the water comes out of the hose with a speed of 7.0 feet per second. if you then put your thumb over the end of the hose so the opening is only a circle 0.25" across, with what speed will the water stream out now?

= initial pressure

= final pressure = 2

= initial volume

= final volume = /4

= initial temperature = 20 c = 20 + 273 = 293 k

= final temperature = ?

using the equation

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.