Trade Science

Question 1

What does a Class 3 Lever look like?

Answer 1

Fulcrum is at the end. Effort is in the center. Resistance is at the other end.

Question 2

What is Newtons First Law?

Answer 2

A body at rest will stay at rest and a body in motion will remain in motion at the same speed and in the same direction unless acted on by some unbalanced force.

Question 3

What is Newtons Second Law?

Answer 3

The size of a net force on an object is equal to the product of mass and acceleration of the object.

Question 4

What is Newtons Third Law?

Answer 4

For every action there is an equal and opposite reaction.

Question 5

What is a compound?

Answer 5

The product of two or more atoms that unite chemically. This creates a substance that has properties different from those of the combining elements.

Question 6

What is a Atom?

Answer 6

A singular unit of an Element.

Question 7

What is an Element?

Answer 7

Elements are materials only containing one type of Atom.

Question 8

What are Cohesive Forces?

Answer 8

Like molecules having a strong attraction to one another.

Question 9

What are Adhesive Forces?

Answer 9

The attraction of unlike molecules.

Question 10

What is the Equation for Density?

Answer 10

Density = Mass/Volume

Question 11

Define Tensile Strength

Answer 11

The ability of a material to resist being pulled apart by external forces.

Question 12

Define Ductility

Answer 12

The ability of a material to stretch and maintain a new shape.

Question 13

Define Malleability

Answer 13

The ability of a material to be permanently deformed by compressive forces.

Question 14

Define Toughness

Answer 14

The ability of a material to withstand shock loads.

Question 15

Define Hardness

Answer 15

A materials ability to resist a force that is trying to penetrate it.

Question 16

What is the rule of thumb for expansion and contraction of steel?

Answer 16

For every 150F change in temp, each inch of diameter and length changes by 0.001 inches

Question 17

Starting from Aluminum name all the Galvanic Series Metals.

Answer 17

Aluminum
Magnesium
Chromium Iron and Steel
Cast Iron
Cadmium
Nickel
Tin
Lead
Brass
Copper
Bronze
Copper-nickel
Silver
Platinum
Gold

Question 18

Define Viscosity

Answer 18

A measure of a liquids resistance to flow.

Question 19

The higher the viscosity of a fluid means what?

Answer 19

The greater it’s resistance to being poured.

Question 20

What are the common units for gas under pressure?

Answer 20

• Pascal = Pa or Kilopascal = kPa
• pounds force per square inch = lbf/in^2 Or psi

Question 21

What does psig stand for?

Answer 21

Pounds per square inch gauge

Question 22

What does psia stand for?

Answer 22

Pounds per square inch absolute

Question 23

What is ATM?

Answer 23

A unit used to describe the average pressure exerted by earths atmosphere at sea level.

Question 24

What is 1 ATM equal to in kPa? What about bar? What about psi?

Answer 24

1 ATM = 101.35 kPa = 1 bar = 14.7 psi

Question 25

What is the absolute temperature scale for Celsius?

Answer 25

Kelvin

Question 26

What is the absolute temperature scale for Fahrenheit?

Answer 26

Rankine

Question 27

What are the units used to measure heat?

Answer 27

Joules (J) Kilojoules (kJ) British Thermal Unit (Btu)

Question 28

What is a Btu?

Answer 28

Heat needed to change 1lb of water by 1 Fahrenheit

Question 29

What is 1 kilojoule equal to in Btu?

Answer 29

1 kJ = 0.948 Btu

Question 30

What is 1 joule equal to in Newton meters?

Answer 30

1 J = 1 N•m

Question 31

What are the three ways heat travels from one object to another?

Answer 31

Conduction, Convection, Radiation

Question 32

What is sfpm?

Answer 32

Surface feet per minute. The amount of distance taken with a rotating surface. Used in imperial.

Question 33

What is power?

Answer 33

The rate at which work is done. Work needs displacement.

Question 34

What is the equation for work?

Answer 34

W = F•d Force times displacement

Question 35

What is 1 Watt equal to in joules/sec?

Answer 35

1W = 1 J/s

Question 36

What is 1 hp = in Watts

Answer 36

1 hp = 746 W

Question 37

What is 1 hp equal to in footpounds per second?

Answer 37

1 hp = 550 ft.lbf/s

Question 38

How do you calculate the Mechanical Advantage of a belt drive?

Answer 38

MA = driver diameter /drive diameter

Question 39

How to do you find Mechanical Advantage of a Chain or Gear Drive?

Answer 39

MA = # teeth on driven / # teeth on drive

Question 40

Finish this: if the driven element is larger than the drive element, the rpm of the driven shaft is _____ than the rpm of the driver.

Answer 40

Less

Question 41

Give the equation to find Mechanical Advantages of rpm of drive and driven elements.

Answer 41

Rpm drive x diameter drive = Rpm driven x diameter driven

Question 42

What is the distance of two adjacent threads on a screw called?

Answer 42

Pitch

Question 43

When a screw is turned on full rotation the screw travels a distance equivalent to _______.

Answer 43

The pitch

Question 44

What is the equation for electrical Power?

Answer 44

P = Voltage x Current P = V x I

Question 45

What type of drill is often used in drilling concrete holes?

Answer 45

Carbide Twist Drills