Question

Which kind of simple machine is the beater part of a mixer?
A) Pulley
B) Wheel-and-axle
C) Pulley and lever
D) Two pulleys

Answer 1

Hint: First of all we need to know the types of simple machines. After that we should know about the working of beaters. Basically, there are six types of simple machines.
1. Wheel and axle
2. The lever
3. The inclined plane
4. The pulley
5. The screw
6. The wedge

Complete solution:
Now, we need to find out the purpose of a beater in a mixer. So, the answer is simple. We use beaters to mix the ingredients used for cooking purposes. The beaters continuously hit the ingredients that are to be mixed and in doing so the beaters have to rotate.
Now at this point we know that the beaters need to rotate, so we need to find which simple machine listed above can be used for this purpose.
Out of the given types, we find that the rotatory motion can be given by the wheels. Now, when the wheels are attached to an axle, it can turn itself freely about the axle. Due to this technique only we find carts’, wagons’, vehicles’ wheels moving.
As we discussed, in a mixer the beater has to rotate along its axis and mix the ingredients, so out of the given options wheel and the axle is the correct option.

Hence, wheel and axle is the simple machine that is used in the beater part of the mixer.

Note: We can get confused by the pulley as well. But we need to be clear that pulley cannot provide complete rotation about the axis.