Machine Design

A heavy rotating body which serves as reservoir for absorbing and redistributing kinetic energy

• A. shaft

• B. flywheel

• C. governor

• D. puncher

It equalizes the energy exerted and the work done thus preventing excessive or sudden changes of speed:

• flywheel

• flywheel pulley

• balance wheel

• all of these

A flywheel has a mean diameter of 4 ft and is required to handle 2200 ft-lb of kinetic energy. The flywheel has a width of 8in. Normal operating speed is 300 rpm and the coefficient of fluctuation is to be 0.05. Find the weight of the rim assuming that the arms and hub are equivalent is 10% of the specific weight.

• 412 lb

• 452.4 lb

• 334 lb

• 533 lb

Answer explanation

Which of the following is used to change the direction of an applied tensile force?

• Gears

• Pulleys

• Flywheels

• Ropes

A punching machine flywheel accelerates from rest at 5 rad/s². How many revolutions does it make in 5 seconds

• 9.947 rev

• 2.45 rev

• 10.54 rev

• 3.42 rev

Answer explanation

The cast iron flywheels are commonly designed with a factor of safety of

• A.14 to 15

• B. 10 to 13

• C. 8 to 9

• D. 6 to 12

A cast iron flywheel with a mean diameter of 36 inches changes speed from 300 rpm to 280 while it gives up 8000 ft-lb of energy. What is the coefficient of fluctuation

• 0.069

• 0.015

• 0.020

• 0.082

Answer explanation

A flywheel rotates at 120 rpm or 12.57 rad/sec slowed down to 102 rpm or 10.68 rad/sec during the punching operation that requires 4 second of the punching portion of the cycle. Compute the angular acceleration of the flywheel in rad/sec².

• -2.52 rad/sec²

• 3.15 rad/sec²

• -2.75 rad/sec²

• 2.22 rad/sec²

Answer explanation

The flywheel on a press rotating at 100 rpm is slowed down to 90 rpm during a punching operation that requires 1 second for punching portion of the system cycle. Compute the angular deceleration in rad/sec-see the flywheel undergoes. Given the angular velocities for 120 rpm is 10.47 rad/sec. And for 90 mph 9.42 rad/sec

• -1.36

• -1.26

• -1.05

• -0.93

Answer explanation

A type of rope construction used for high-speed elevator applications

• 6 x 7

• 6 x 37

• 6 x 19

• 8 x 19

Answer explanation