The nebular theory states that star systems form by the gravitational collapse of a cloud of gas and dust that, to match observations, must flatten into a disk within which planets can form. why would this flattening occur? consider the law of conservation of angular momentum, which states that a quantity related to the size of an object (its moment of inertia) times the speed of rotation (angular speed) has to remain the same at all times as long as no outside forces act on that object. based on this law, if a collapsing cloud is isolated in space with no external forces, what must happen to it as its size decreases?

it is called kinetic energy

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods

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.