Question

Which of the following is an example of an inclined plane?

• A. Nutcracker
• B. Road in hilly area
• C. Scissor
• D. Knife

Answer 1

The correct option is B

Road in hilly area

Explanation for the correct option

Option B: road in a hilly area

1. To climb to the top of the hill, we can not make the straight road as it will be a steep slope.
2. The angle between the inclined plane and horizontal surface and thereby the effort required will also be very large. $\mathrm{Mechanical}\mathrm{advantage}=\frac{\mathrm{length}\mathrm{of}\mathrm{inclined}\mathrm{plane}}{\mathrm{vertical}\mathrm{height}}=\frac{\mathrm{load}}{\mathrm{effort}}$
3. When the winding hill road is constructed it provides us with a gentle slope and gradually the vehicle rises towards the top of the hill, which makes effort also to be of very low magnitude because the effort is directly proportional to vertical height.

Explanation for the incorrect options

Option A: nut cracker

1. It belongs to class 2 levers.
2. Class 2 levers consist of those machines which have a load in between the fulcrum and effort.
3. In the case of a nut cracker, the fulcrum is shown at the end of two parts of nut cracker.
4. The effort is applied by hands in the opposite direction at the handle portion.
5. The nut is placed in between the portion to get destroyed by the force.

Option C: scissors

1. Scissors are modifications of the lever of the first order.
2. It consists of two sharp knives, provided with handles and pivoted at the center.
3. It is used for cutting cloth, leather, paper, thread, rubber, and plastic.

Option D: knife

1. It belongs to class 3 levers.
2. It is made of two parts, i.e., a handle made of plastic or wood and a blade made of steel, such that its one edge is very sharp.
3. By holding the knife by the handle, we can cut fruit, vegetables, meat, fish, etc.

Thus, a road in a hilly area is an example of an inclined plane.

Hence, option (B) is correct.