Question

Which of the following is a third order lever?
A. Crowbar
B. Nutcracker
C. Scissors
D. Tongs

Answer 1

The given question asks us which of the above examples of third order levers is. So, to find the answer we will first have to find out what are third order levers then further we will find which of the above have the properties as of the third order lever and thus we will reach our answer.

Complete step-by-step solution: -
In the above question where we have to find which of the above is third order lever, we will first discuss what is third order lever then only we can proceed further.
A third order lever is the one which has its effort between the fulcrum and the load. Such levers do not have good mechanical advantages. In fact, they have more mechanical disadvantages. As we know that the effort is closer to the fulcrum than the load. The effort will always be greater than the load. However, one advantage of third order levers is that the distance moved by the load will be greater than that of the distance moved by the effort.
Tongs are examples of levers that make it easy to lift or remove the items, even though the items aren't very heavy. Tweezers and tongs are the third order levers because the fulcrum is at one end and the load is at the other. We have to use human effort in the center of the lever to pinch the tweezers or tongs to grasp and lift or remove materials.
Tongs are third order Levers as they reduce the applied force and hence helps in providing better control and manipulation. In these, as we know that the effort and the load are on the same side of the fulcrum, however, the effort is closer to the fulcrum so it demands more force to move light weights.
So, by the above discussion we got to know that option (D) , that is tong is the correct answer as it is the example of third order levers.

Note: The discussion above tells us about the third order levers which are defined as the one which has its effort between the fulcrum and the load. Also here, crowbar and scissors are examples of first order levers and nutcracker is an example of second order levers.