Question

Which of the following simple machines are combined to make scissors?
A). Wedge and pulley
B). Lever and gear
C). Lever and wedge
D). Gear and pulley

Answer 1

Hint: A scissor is a compound machine, which means that it is made up of a combination of two or more simple machines. A scissor consists of a pair of blades and handles that are joined together by a screw which forms the pivot point. The blades help in cutting objects when a person applies force on the handles.

Complete step by step answer:
A scissor is a compound machine that is used for cutting objects. A compound machine is a machine that is made up of a combination of two or more than two simple machines such as wedge, pulley, lever, gear, wheel and axle.
A scissor consists of two blades that are shaped in the form of wedges and two handles. The handles and blades are connected together at a common pivot point, which is usually a screw. This pivot point acts as the fulcrum of the two lever arms, that is, the blades and the handles.
Hence, a scissor is essentially a lever along with a wedge in the form of the blades. Hence, a scissor is made of the simple machines, lever and wedge.
Hence, the correct option is C) lever and wedge.

Note: Students should be able to identify different types of simple machines when analyzing a compound machine. This can only be possible if the student knows the properties, structures and functioning of each of the six simple machines, wheel, axle, wedge, lever, gear and pulley. Each simple machine has a different unique purpose and a compound machine can be made by a combination of these simple machines, which serves a different bigger purpose in itself.