Which of the following is an example of a conversion from heat to mechanical energy? 1. steam engine 2. toaster 3. generator 4. windmill

1.Steam engines

Explanation:

Steam engines are heat engines which uses steam as a fluid to perform mechanical work. The pistons in the cylinders pushed back and forth using the force created by the pressure of steam. With help of connecting rod and flywheel, this pushing force is transferred to rotational work. Hence, steam engine transforms heat into mechanical work.