Deck 6: Power

Question 1

What type of energy does compressed air have?

A) potential energy
B) kinetic energy
C) mechanical energy
D) repressed energy

Answer 1

potential energy

Question 2

Two identically powered trucks, one loaded and one unloaded, complete a 200 mile journey. The loaded truck has twice the GVW of the unloaded truck and completes the journey averaging 55 mph. The unloaded truck completes the journey averaging 60 mph. Which of the two trucks has done the most work?

A) equal
B) the unloaded truck
C) the loaded truck
D) more information is required

Answer 2

the loaded truck

Question 3

Two technicians named A and B, each weighing 200 lbs (90 kgs), jog a distance of one mile (1.6 km). Technician A completes the distance in 15 minutes and technician B completes the distance in 20 minutes. Who has done the most work?

A) Technican A
B) Technician B
C) Work accomplished is equal
D) More information is required

Answer 3

Work accomplished is equal

Question 4

Two technicians named A and B, each weighing 200 lbs (90 kgs), jog a distance of one mile. Technician A completes the distance in 15 minutes and technician B completes the distance in 20 minutes. Which technician has the most power?

A) Technican A
B) Technician B
C) Equal power
D) More information is required

Question 5

Which of the following is the more accurate way of expressing torque?

A) force
B) work
C) linear effort
D) turning effort

Question 6

What is the force used in a diesel engine to produce mechanical output?

A) air pressure
B) fuel injection pressure
C) cylinder pressure
D) inertia

Question 7

If the length of a crankshaft throw was changed either up or down, which of the following would be directly affected?

A) engine torque
B) engine rpm
C) engine noise
D) engine vibration

Question 8

When James Watt was studying draft horse working ability, how much power did he reckon the horse was capable of lifting?

A) 550 lbs through 100ft in 60 seconds
B) 330 lbs through 100ft in 60 seconds
C) 330 lbs through 10ft in 60 seconds
D) 550 lbs through 1000ft in 60 seconds

Question 9

When comparing work accomplished with power, which of the following helps define power but has nothing to do with work?

A) torque
B) force
C) weight
D) time

Question 10

In a modern diesel engine, what percentage of total power is typically consumed in overcoming pumping and frictional losses?

A) 5%
B) 10%
C) 15%
D) 20%

Question 11

What is the rate of performing work known as?

A) torque
B) energy
C) power
D) effort

Question 12

One hundred Newton meters are equal to:

A) 135.6 lb/ft
B) 13.56 lb/ft
C) 737 lb/ft
D) 73.7 lb/ft

Question 13

Which of the following best describes the mechanical role of a crankshaft throw in relation to the crankshaft centerline?

A) link
B) lever
C) offset
D) journal

Question 14

What terms do truck diesel engine manufacturers use to rate the power of their engines?

A) brake horsepower
B) indicated horsepower
C) kilowatts
D) peak torque

Question 15

Which of the following methods of measuring horsepower when applied to the same engine will usually produce the lowest rating?

A) indicated horsepower
B) calculated horsepower
C) brake horsepower
D) SAE horsepower

Question 16

A Mack Trucks MP8 engine is rated at 335 kilowatts brake power. Convert to horsepower:

A) 350 BHP
B) 400 BHP
C) 450 BHP
D) 500 BHP

Question 17

A Cummins ISX is rated at 625 BHP. Convert to kilowatts:

A) 448 kw
B) 466 kw
C) 485 kw
D) 493 kw

Question 18

A Detroit Diesel DD15 engine dynamometer tests at 505 BHP. Convert to kilowatts:

A) 300 kw
B) 325 kw
C) 335 kw
D) 377 kw

Question 19

Which of the following correctly identifies torque rise rpm?

A) idle to high idle rpm
B) engine lug to peak torque rpm
C) peak torque to rated speed rpm
D) rated speed to high idle rpm

Question 20

Which of the following acronyms is used by manufacturers to indicate actual fuel consumption?

A) Btus per hour
B) BSFC
C) BHP
D) kw/hr

Question 21

330 lb × 100 ft = ____________________ lb/ft per minute = ____________________ lb/ft per second = ____________________ HP

Question 22

Work = ____________________ × ____________________

Question 23

25,450 Btu per hour = ____________________ HP

Question 24

In a diesel engine, force is represented by ___________________________________.

Question 25

When engine power is expressed as brake power, this is usually measured at _________________________.