Mechanical Systems 3

Instructions:

• Answer 50 questions in 15 minutes.
• If you are not ready to take this test, you can study here.
• Match each statement with the correct term.
• Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. How can you decrease friction on flat surfaces?
To speed up the motion of resistence.
Work=Force*Distance
With oil - grease or soap.
your arm.


2. Work is measured in units also known as?
Can change the direction of motion.
Foot- pounds
Equals the weight of the object being hoisted.
Connects shafts having a 90 degree angle.


3. What is the purpose of a third class lever?
fulcrum- weight- effort
To speed up the motion of resistence.
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.
Same.


4. How do you find the mechanical advantage?
Find the resistance weight and divide that by the effort you need to lift the weight. M.A=R/E - This rule applies to all machines.
Can change the direction of motion.
Wheel and axle.
When a resistance is overcome by a force acting through a measurable distance.


5. What kind of machine is the inclined plane?
your arm.
Length of ramp/length of height from floor to truck
Simple machine
A screw and a spur gear.


6. What kind of mechanical advantage does the first and second class lever provide?
Positive mechanical advantage.
Less than 1.
A modification of an inclined plane.
Foot- pounds


7. What is the ratio of any gear train?
your arm.
Two surfaces move against one another.
Gravity - Magnetism - Friction - Recoil
Product of the number of teeth on each of the driver gears/ divided by the product of number of teeth of the driven gear.


8. What is the formula for the mechanical advantage of a screw?
Same.
Positive mechanical advantage.
2(pie)/pitch
Foot- pounds


9. What is the third thing a gear can do?
Length of ramp/length of height from floor to truck
2(pie)/pitch
Same.
Magnify or reduce the force which you apply.


10. What is one type of second class lever?
The force used to overcome friction is greater than the force used to do useful work.
The rope that passes through your hands is greater than the distance that the load is raised.
Wheel and axle.
2(pie)/pitch


11. The miter gear faces are beveled at what angle?
Mechanical disadvantage. Use more force than the force of the load you lift.
45
Wheel and axle.
A few thousandths of an inch.


12. What does a micrometer measure?
Opposite.
A few thousandths of an inch.
Product of the number of teeth on the driven gears/ divided by the product of the number of teeth on the driver gears.
Work=Force*Distance


13. What is the lever formula?
Find the resistance weight and divide that by the effort you need to lift the weight. M.A=R/E - This rule applies to all machines.
In pounds.
1
L/l=R/E Length of effort arm divided by length of resistance arm divided by weight of resistance divided by Effort.


14. What is the formula for the wheel and axle?
L=radius of the circle where the handle turns/l=1/2 the width of the edge of the blade = R=force of resistance offered by the screw/E=effort applied by the handle
32/8 = 4
Can change the direction of motion.
L/l=R/E Length of effort arm divided by length of resistance arm divided by weight of resistance divided by Effort.


15. What is another example of a wheel and axle?
Equals the weight of the object being hoisted.
When a resistance is overcome by a force acting through a measurable distance.
45
Door knob.


16. What is the work formula?
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.
Work=Force*Distance
Two surfaces move against one another.
In Horsepower.


17. What is the theoretical mechanical advantage of any gear train?
L=radius of the circle where the handle turns/l=1/2 the width of the edge of the blade = R=force of resistance offered by the screw/E=effort applied by the handle
Product of the number of teeth on the driven gears/ divided by the product of the number of teeth on the driver gears.
1
A modification of an inclined plane.


18. What direction does the effort and resistance move in first class levers?
Opposite.
To magnify the applied force.
A modification of an inclined plane.
fulcrum- weight- effort


19. How can you figure out the mechanical advantage of most block and falls by glance?
Wheel and axle.
A few thousandths of an inch.
Work=Force*Distance
Count the number of parts of the rope going to and from the movable block.


20. What is the power formula?
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.
Power=Work/Time
Product of the number of teeth on the driven gears/ divided by the product of the number of teeth on the driver gears.
To speed up the motion of resistence.


21. The worm gear is a combination of what?
A screw and a spur gear.
Foot- pounds
L/l=R/E Length of effort arm divided by length of resistance arm divided by weight of resistance divided by Effort.
Direction - speed or size of the force applied.


22. Formula for fractional mechanical disadvantage.
fulcrum- weight- effort
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.
Work=Force*Distance
With oil - grease or soap.


23. For Blocks and falls if you are getting a mechanical advantage what is the distance of your pull and the weights?
The rope that passes through your hands is greater than the distance that the load is raised.
The change of the direction of the pull.
Door knob.
Magnify or reduce the force which you apply.


24. The bevel gear is used to connect what?
Shafts lying at any given angle.
Magnify or reduce the force which you apply.
Work=Force*Distance
In pounds.


25. What is the mechanical advantage of a single movable block?
L=radius of the circle where the handle turns/l=1/2 the width of the edge of the blade = R=force of resistance offered by the screw/E=effort applied by the handle
2. Each half of the rope carries an equal amount of weight.
Foot- pounds
Direction - speed or size of the force applied.


26. What is the jack screw used for?
A few thousandths of an inch.
Power=Work/Time
fulcrum- weight- effort
To raise a house or other heavy machinery.


27. What direction does the effort and resistance move in the second class levers?
Shafts lying at any given angle.
Foot- pounds
Same.
Simple machine


28. What is an example of a third class lever?
Mechanical disadvantage. Use more force than the force of the load you lift.
When a resistance is overcome by a force acting through a measurable distance.
Simple machine
your arm.


29. What are first and third class levers used for?
A modification of an inclined plane.
Count the number of parts of the rope going to and from the movable block.
To magnify the applied force.
Length of ramp/length of height from floor to truck


30. Belt drive Gear 1 has 32 teeth and gear 2 and 3 have 8 teeth - for 1 revolution that gear 1 makes how many revolutions do gears 2 and 3 make?
32/8 = 4
Work=Force*Distance
Less than 1.
Mechanical disadvantage. Use more force than the force of the load you lift.


31. How do you measure power?
Foot- pounds
Count the number of parts of the rope going to and from the movable block.
In Horsepower.
Equals the weight of the object being hoisted.


32. What are the 4 forces?
Gravity - Magnetism - Friction - Recoil
Product of the number of teeth on the driven gears/ divided by the product of the number of teeth on the driver gears.
Find the resistance weight and divide that by the effort you need to lift the weight. M.A=R/E - This rule applies to all machines.
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.


33. With a single fixed sheave on a block and tackle what must the force of your down pull equal?
A screw and a spur gear.
Work=Force*Distance
Equals the weight of the object being hoisted.
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.


34. Gears can do a job for you by changing what three things?
Can change the direction of motion.
Wheel and axle.
To raise a house or other heavy machinery.
Direction - speed or size of the force applied.


35. What is the second thing a gear can do?
Two surfaces move against one another.
Same.
Increase or decrease the the speed of the applied motion.
To magnify the applied force.


36. hat is a screw?
A modification of an inclined plane.
Equals the weight of the object being hoisted.
Product of the number of teeth on each of the driver gears/ divided by the product of number of teeth of the driven gear.
To speed up the motion of resistence.


37. With a single fixed sheave what is the only mechanical advantage?
The change of the direction of the pull.
Third class lever.
Shafts lying at any given angle.
32/8 = 4


38. Fractional mechanical advantage
Mechanical disadvantage. Use more force than the force of the load you lift.
To speed up the motion of resistence.
Increase or decrease the the speed of the applied motion.
Can change the direction of motion.


39. The threads of a screw are cut so?
The force used to overcome friction is greater than the force used to do useful work.
To raise a house or other heavy machinery.
Two surfaces move against one another.
45


40. How is work done?
Can change the direction of motion.
Work=Force*Distance
Equals the weight of the object being hoisted.
When a resistance is overcome by a force acting through a measurable distance.


41. What is the first thing a gear can do?
Product of the number of teeth on each of the driver gears/ divided by the product of number of teeth of the driven gear.
In pounds.
Can change the direction of motion.
Shafts lying at any given angle.


42. What is the mechanical advantage for a single fixed block?
1
your arm.
Length of ramp/length of height from floor to truck
Two surfaces move against one another.


43. What is another way to find the mechanical advantage of an inclined plane?
Product of the number of teeth on the driven gears/ divided by the product of the number of teeth on the driver gears.
Find the resistance weight and divide that by the effort you need to lift the weight. M.A=R/E - This rule applies to all machines.
Length of ramp/length of height from floor to truck
Same.


44. What type of lever provides a fractional mechanical advantage?
Length of ramp/length of height from floor to truck
To raise a house or other heavy machinery.
Third class lever.
1


45. How is force measured in work?
The force used to overcome friction is greater than the force used to do useful work.
In pounds.
Simple machine
Third class lever.


46. An egg beater has a mechanical advantage of what?
Feet.
Less than 1.
Product of the number of teeth on the driven gears/ divided by the product of the number of teeth on the driver gears.
Effort arm/Resistance arm - A/a - An expression of the ratio of the applied force and the resistance.


47. Friction is involved when?
Magnify or reduce the force which you apply.
Two surfaces move against one another.
Power=Work/Time
32/8 = 4


48. What direction does the effort and resistance move in third class levers.
Find the resistance weight and divide that by the effort you need to lift the weight. M.A=R/E - This rule applies to all machines.
Third class lever.
Same.
Power=Work/Time


49. Class two lever
To raise a house or other heavy machinery.
A modification of an inclined plane.
Increase or decrease the the speed of the applied motion.
fulcrum- weight- effort


50. How is distance measured in work?
Feet.
Connects shafts having a 90 degree angle.
In Horsepower.
Door knob.