Gear contact is a which type of pair?

Gear contact is a rolling pair.

Explanation:
Gear contact refers to the interaction between two gears when they are in mesh. Gears are mechanical elements that transmit motion and power between rotating shafts. They consist of toothed wheels that engage with each other to transfer rotational motion.

Types of Pairs:
In kinematics, pairs are classified into different types based on the nature of their relative motion. The four main types of pairs are:

1. Higher Pair:
- A higher pair is formed when two elements have surface contact with each other.
- The relative motion between the elements is a combination of both sliding and rolling.
- Examples of higher pairs include a screw and nut, a shaft and bearing, etc.

2. Lower Pair:
- A lower pair is formed when two elements have line or point contact with each other.
- The relative motion between the elements is primarily a combination of sliding and/or turning.
- Examples of lower pairs include a cylindrical roller bearing, a pin joint, etc.

3. Rolling Pair:
- A rolling pair is a type of lower pair.
- It is formed when two elements have point contact and rolling motion with respect to each other.
- The contact between the elements occurs along a line or a point, and the relative motion is purely rolling.
- Examples of rolling pairs include gears, rolling bearings, rolling wheels, etc.

4. Turning Pair:
- A turning pair is another type of lower pair.
- It is formed when two elements have line or point contact and the relative motion is primarily turning.
- The contact between the elements occurs along a line or a point, and the relative motion is primarily rotational or turning.
- Examples of turning pairs include a shaft in a bearing, a cam and follower, etc.

Conclusion:
Gear contact is classified as a rolling pair because the interaction between gears involves point contact and pure rolling motion. Gears transmit motion and power through the engagement of their teeth, which roll against each other without any sliding or turning motion.

Higher pair as well as rolling pair also.