AUT 101-Chapter 3 Question and Key Terms

Bases-

Any of a class of compounds that form hydroxyl ions (OH) when dissolved in water, and whose aqueous solutions react with acids to form salts

5. Describe four different types of energy conversion.

Chemical to Thermal, Chemical to Electrical, Electrical to Mechanical and Thermal to Mechanical.

4. Describe five different forms of energy.

Chemical, Thermal, Electrical, Mechanical and Radiant

25. Which of the following is not a true statement about heat transfer?

Conduction is the transfer of heat by infrared rays

21. While discussing friction in matter: Technician A says that friction creates heat. Technician B says that friction only occurs with solids and is not present with liquids and gases. Who is correct?

Technician A only

2. In what four states does matter exist? Cite examples of each.

The four states of matter are solid, liquid, gas and plasma. The atoms in a solid are tightly bound to each other, either in a regular geometric lattice (crystalline solids, which include metals and ordinary ice) or irregularly (an amorphous solid such as common window glass). A liquid, like a gas, displays the properties of a fluid. A liquid can flow, assume the shape of a container, and, if placed in a sealed container, will distribute applied pressure evenly to every surface in the container. Water is a good example of a liquid. Gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). A plasma can be created by heating a gas or subjecting it to a strong electromagnetic field applied with a laser or microwave generator. The sun is an example of plasma.

9. Describe the effect of pressure on an enclosed volume of a gas.

The pressure of a gas in a volume increase or decrease in relationship to its temperature. Increasing the temperature of the gas will increase its pressure.

Catalyst-

a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change

Electromagnet-

a wire that is wrapped around an iron bar with current running through it

Acids-

are compounds that break into hydrogen ions and another compound when placed in an aqueous (water) solution

19. Vacuum is defined as the absence of _______________.

atmospheric pressure

15. When one object is moved over another object, the resistance to motion is called ___________.

friction

16. Weight is the measurement of the earth's ____________ on an object.

gravitational pull

23. When applying the principles of work and force, _______________________.

if a 50-pound object is moved 10 feet, 500 ft lb of work are produced

Lever-

is a device made up of a bar pivoting on a fixed point called the fulcrum

Gas-

is a fluid made up of independent particles-atoms or molecules- that are in constant, random motion

Pressure-

is a force applied against an object and is measured in units of force per unit of surface area

Centripetal force-

is a force that makes a body follow a curved path. Its direction is always orthogonal to the motion of the body and towards the fixed point of the instantaneous center of curvature of the path

Torque-

is a force that rotates or turns things and is measured by the force applied and the distance traveled

Heat-

is a form of energy

Carburizing-

is a heat treatment process in which iron or steel absorbs carbon liberated when the metal is heated in the presence of a carbon bearing material, such as charcoal or carbon monoxide, with the intent of making the metal harder

Mechanical advantage-

is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Ideally, the device preserves the input power and simply trades off forces against movement to obtain a desired amplification in the output force

Engine efficiency-

is a measurement of the amount of energy put into the engine and the amount of energy available from the engine

Power-

is a measurement of the rate, or speed, at which work is done

Alloy-

is a mixture of two or more metals

Solution-

is a mixture of two or more substances

Hardening-

is a process that increases the hardness a metal, deliberately or accidentally, by hammering, rolling, carburizing, heat treating, tempering, or other processes

Density-

is a statement of how much mass there is in a particular volume

Electrolyte-

is a substance that conducts current as a result of the breaking down of its molecules into positive and negative ions

Gear-

is a toothed wheel that becomes a machine when it is meshed with another gear

Pulley-

is a wheel with a grooved rim in which a rope or belt conveys the force from another pulley to move something

Ion-

is an atom or molecule that has lost or gained one or more electrons

Electrolysis-

is an electrochemical process

Centrifugal Force-

is an outward force apparent in a rotating reference frame; it does not exist when measurements are made in an inertial frame of reference. All measurements of position and velocity must be made relative to some frame of reference

Matter-

is anything that occupies space

Kinetic energy-

is energy that is released to do work

Hertz (Hz)-

is equal to one cycle per second

Vacuum-

is the absence of atmospheric pressure

Mass-

is the amount of matter in an object

Oscillation-

is the back-and-forth movement of an object between two points

Speed-

is the distance an object travels in a set amount of time

Tempering-

is the heat treating of metal alloys, particularly steel

Specific gravity-

is the heaviness of relative density of a substance as compared to water

Conduction-

is the movement of heat through a material

Force Frequency-

is the number of times a vibration occurs in 1 second

Static pressure-

is the pressure in a balanced hydraulic system

Momentum-

is the product of an object's weight and speed

Horsepower-

is the rate at which torque is produced

Acceleration-

is the rate of increase in speed

Tensile Strength-

is the ratio of the maximum load a material can support without breaking while being stretched

Deceleration-

is the reverse of acceleration; it is the rate of a decrease in speed

Molecule-

is the smallest particle of an element or compound

Velocity-

is the speed of an object in a particular direction

Aerodynamics-

is the study of the effects of air on a moving object

Inertia-

is the tendency of an object at rest to remain at rest or the tendency of an object in motion to stay in motion in one direction

Thermal expansion-

is the tendency of matter to change in volume in response to a change in temperature, through heat transfer

Gross weight-

is the total weight of the vehicle when it is fully loaded with passengers and cargo

Convection-

is the transfer of heat by the movement of a heated object

Curb weight-

is the weight of the vehicle when it is not loaded with passengers or cargo

pH scale-

is used to measure how acidic or basic a solution is

Permeable-

material that absorb fluids

Atmospheric pressure-

may be defined as the total weight of the earth's atmosphere.

Reduction-

occurs during oxidation and which the end result is that one substance is oxidized by the other is reduced in the process

Dynamic pressure-

pressure of the fluid while it is in motion

10. The nucleus of an atom contains _________ and _________.

protons, neutrons

Plasma-

refers to an ionized gas that has about an equal amount of positive ions and electrons

Equilibrium-

results when the applied forces are balanced and there is no overall resultant force

Potential energy-

stored energy

Impermeable-

substance that adsorb fluids

Element-

substance with only one type of atom

Thermal contraction-

takes place when a mass has heat removed from it and the atoms and molecule slow down

Volume-

the amount of space that a substance or object occupies, or that is enclosed within a container, especially when great

Barometric pressure-

the change in atmospheric pressure

Radiation-

the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization

Tension-

the force pulling on solid moving atoms farther apart

Latent heat-

the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature

Solvent-

the liquid in which a solute is dissolved to form a solution

Amplitude-

the maximum extent of a vibration or oscillation, measured from the position of equilibrium

Oxidation-

the process or result of oxidizing or being oxidized

Diffusion-

the random movement of gas particles sharing the same container that mix together

Evaporate-

the solid that is left behind after all the liquid has evaporated

Displacement-

the volume the cylinder holds between the top dead center and bottom dead center positions of the piston

Load-

the work an engine must do, under which it operates more slowly and less efficiently

24. All these statements about energy and energy conversion are true, except _______________________.

thermal energy may be defined as light energy

17. Torque is a force that does work with a ___________ action.

twisting

13. Energy may be defined as the ability to do _________.

work

11. Which of the following is the correct formula used to calculate engine displacement?

Displacement=π x R2 x L x N

6. Explain why a rotating, tilted wheel moves in the direction of the tilt.

Because the centerline of the wheel is in the direction of the tilt the wheel will move in relation to it.

7. Why are gases and liquids considered fluids?

Because the characteristic of fluids is that they will conform to the shape of the container just like gases and liquids.

12. Work is calculated by multiplying _________ by __________.

Force, Distance

8. Describe how out-of-balance forces can affect the automobile.

Improper balance can cause premature wear or destruction of parts such as the uneven wear on tire if not correctly balanced.

14. Name three types of simple machines.

Inclined plane, pulleys and levels

20. While discussing different types of energy: Technician A says that when energy is released to do work, it is called potential energy. Technician B says that stored energy is referred to as kinetic energy. Who is correct?

Neither A nor B

22. While discussing mass and weight: Technician A says that mass is the measurement of an object's inertia. Technician B says that mass and weight may be measured in cubic inches. Who is correct?

Neither A nor B

1. Describe Newton's first law of motion and give an application of this law in Automotive Technology.

Newton's first law of motion states that an object at rest tends to remain at rest and object in motion tends to remain in motion. When a car is parked on a level street, it remains stationary unless it is driven or pushed.

3. Explain Newton's second law of motion and give an example of how this law is used in automotive theory.

Newton's second law of motion states that when a force acts on an object, the motion of the object, the motion of the object will change. Trucks have a greater mass than cars. Because of the large mass requires larger force to produce a given acceleration, a truck needs a more powerful engine than a car.

Heat treating-

changes the properties of a metal by using heat

Atoms-

countless tiny particles that made up matter

Compression ratio-

expresses how much the air and fuel mixture is compressed as a cylinder's piston moves from the bottom to the top of the cylinder