Assertion A: For a given depth of cut, the output of a power shovel can be increased by decreasing the angle of swing. Reason R: If the angle of swing is decreased, the cycle time will be decreased. A. Both A and R is true and R is the correct explanation of A B. Both A and R is true but R is not the correct explanation of A C. A is true but R is false D. A is false but R is true

The correct answer is: Both A and R is true but R is not the correct explanation of A.

The assertion A is true because the angle of swing is one of the factors that affects the cycle time of a power shovel. The smaller the angle of swing, the shorter the cycle time. This is because the power shovel will not have to travel as far to dump the load.

However, the reason R is not the correct explanation of A. The cycle time is affected by a number of factors, including the angle of swing, the distance to the dump point, and the load weight. Therefore, even if the angle of swing is decreased, the cycle time may not decrease if the other factors are not also changed.

For example, if the distance to the dump point is increased, the cycle time will increase even if the angle of swing is decreased. This is because the power shovel will have to travel further to dump the load.

Therefore, the correct answer is: Both A and R is true but R is not the correct explanation of A.