Engineering Questions with Answers - Multiple Choice Questions

# MCQs on Heads in a Turbine

1 - Question

Among the following which turbine requires more head?
a) Pelton Turbine
b) Kaplan Turbine
c) Francis turbine
d) Tube Turbine

a
Explanation: Except Pelton remaining are reaction turbines, in impulse pressure energy is constant and only available energy is kinetic energy which is directly proportional to head.

2 - Question

d

3 - Question

Head under which Kaplan turbine is operated______
a) 10-70 meters
b) 70 -100 meters
c) 100-200 meters
d) Above 200 meters

a
Explanation: Kaplan turbine is reaction turbine and it operates at low head 10-70 meters and output power is 5-200 MW.

4 - Question

Head under which Francis turbine is operated?
a) 10-70 meters
b) 70-100 meters
c) 100-200 meters
d) 40-600 meters

d
Explanation: Francis turbine is also reaction turbine but pressure energy is less when compared with Kaplan turbine. Hence head is between 40 and 600 meters.

5 - Question

The turbine is preferred for 0 to 25 m head of water?
a) Pelton wheel
b) Kaplan turbine
c) Tube turbine
d) Francis turbine

b
Explanation: Kaplan is reaction turbine and its range of operation is between 10-70 meters which has output range between 5-200 MW.

6 - Question

Under what head is Pelton turbine operated?
a) 20-50 meters
b) 15-2000 meters
c) 60-200 meters
d) 50-500 meters

b
Explanation: Pelton turbine is an impulse turbine only energy available is kinetic energy which is proportional to head, hence it requires high head. Theoretically there is no limit to max value of head.

7 - Question

_____________ is difference between head race and tail race.

a
Explanation: Gross head is the difference in elevation of water levels of fore bay and tail race.

8 - Question

The head available at inlet of turbine is ____________

c
Explanation: It is the available effective head used for production. This is also called as static gross head.

9 - Question

Head lost due to friction is given by k*f*L*v*v/D*2g where f- friction coefficient, L- length of pen stock, D- diameter of penstock and” k” is constant and its value is ____________
a) 2
b) 3
c) 4
d) 5

c
Explanation: The constant determined from the given formula is 4.

10 - Question

The difference between gross head and friction losses is ____________