To solve the given question, we need to understand the composition and uses of cast iron. Cast iron is an alloy of iron that contains 2-4% carbon and varying amounts of silicon and manganese. It is known for its excellent machining properties and resistance to deformation. Cast iron is used as a primary material in the manufacturing of various products due to its cost-effectiveness and desirable properties. Below is a detailed explanation of the options given:
Hence, the correct answer is Option 4: pig iron, scrap iron, and steel.
A block of mass 1 kg is pushed up a surface inclined to horizontal at an angle of \( 60^\circ \) by a force of 10 N parallel to the inclined surface. When the block is pushed up by 10 m along the inclined surface, the work done against frictional force is:

[Given: \( g = 10 \) m/s\( ^2 \), \( \mu_s = 0.1 \)]
A gas can be taken from A to B via two different processes ACB and ADB. When path ACB is used, \( 60 J \) of heat flows into the system and \( 30 J \) of work is done by the system. If path ADB is used, the work done by the system is \( 10 J \). The heat flow into the system in path ADB is:
