In a Porter governor, the balls are attached to the extension of lower links.Porter governor is a modification of Watt's governor, with a central load attached to the sleeve.A Hartnell governor is a spring loaded governor.

Cause all weight are loaded. on. spring. and all balance ND adjustment of engine speed is all done by spring adjustment

Spring Loaded Governor
The correct answer is option C, a spring-loaded governor. A Hartnell governor is a type of centrifugal governor that uses springs to control the speed of an engine or machine. Here is a detailed explanation of a spring-loaded governor:

Centrifugal Governor
A centrifugal governor is a device used to automatically regulate the speed of an engine by controlling the amount of fuel or steam supplied to it. It operates based on the principle that the centrifugal force generated by rotating masses is proportional to the speed of rotation.

Hartnell Governor
A Hartnell governor is a specific type of centrifugal governor that utilizes springs to exert a force on the rotating masses. The springs are used to counteract the centrifugal force and maintain a stable speed for the engine or machine.

Functionality
When the speed of the engine increases, the centrifugal force acting on the rotating masses also increases. This causes the springs to compress, exerting a force in the opposite direction. As a result, the throttle of the engine is adjusted to reduce the amount of fuel or steam supplied, thus bringing the speed back to the desired level.

Advantages
- Provides automatic speed regulation
- Simple design and reliable operation
- Effective in controlling the speed of engines and machines
In conclusion, a Hartnell governor is a spring-loaded centrifugal governor that is commonly used in various applications to maintain a constant speed. It is an essential component in ensuring the efficient operation of engines and machinery.