Explanation: A machine with lower efficiency has more losses, and therefore increased operating cost. Also, losses cause heating of the machine and therefore, its temperature rise. Similarly, voltage drop IR is associated with ohmic loss. 2. To determine the efficiency of the machine, direct load test is not advantageous because of which of the following reasons?
A. Cost of providing large inputs
B. Difficulty of dissipating the large outputs
C. Both cost of providing large inputs and difficulty in dissipating the large outputs
D. None of the mentioned
Answer:A
Explanation: A machine with lower efficiency has more losses, and therefore increased operating cost. Also, losses cause heating of the machine and therefore, its temperature rise. Similarly, voltage drop IR is associated with ohmic loss. 2. To determine the efficiency of the machine, direct load test is not advantageous because of which of the following reasons?
A. Cost of providing large inputs B. Difficulty of dissipating the large outputs C. Both cost of providing large inputs and difficulty in dissipating the large outputs D. None of the mentioned
Explanation: Also, a small error in the measurement of either output or input causes the same amount of error in the computed efficiency. 3. Which of the following statements are correct regarding brush contact losses?