Exercise 5

Question 0

What are the swirling currents called hat are induced in transformers and produce heat losses?

Answer 0

Eddy currents

Question 1

What is it called when a solenoid has an iron core in its center?

Answer 1

An electromagnet

Question 2

What is a permeable material?

Answer 2

Materials that are easily magnetized and demagnetized.

Question 3

If a step down transformer has a turns ratio of 1:10, what will the output voltage be if the input voltage is 220V?

Answer 3

22V

Question 4

What is the atomic number of an atom equal to?

Answer 4

The number of protons

Question 5

What type of radiation is produced when a high speed electron is slowed down or suddenly stopped?

Answer 5

Bremsstrahlung radiation

Question 6

How many angstroms are in a meter?

Answer 6

10,000,000,000

Question 7

What type of transformer has more turns of wire in the secondary side than the primary side?

Answer 7

Step-up transformer

Question 8

How you you figure out what the root mean square (RMS) value is on a single phase unit?

Answer 8

Multiply .707 by the kilovoltage peak

Question 9

What type of bond holds atoms together because of their charge?

Answer 9

Ionic bond

Question 10

What type of transformer core is most widely used in radiographic equipment? Why?

Answer 10

Shell type because it has it’s primary and secondary coils wrapped on top of each other maximizing the effects if the mutual induction

Question 11

When were X-rays discovered?

Answer 11

November 8 1895

Question 12

Describe a generator?

Answer 12

A coil of wire rotating through a magnetic field and produces an electric current

Question 13

What is energy loss, caused as magnetic domains rearrange in a transformer in the form of heat, called?

Answer 13

Hysteresis losses

Question 14

What is the major reason for using an alternating current?

Answer 14

Transformers cannot work without it. Alternating currents create the fluctuating magnetic fields a transformer needs to transfer energy from the primary side to the secondary side.

Question 15

What is the formula for electrical power?

Answer 15

P=VI

Power=Voltage x Amperage

Question 16

In the normal diagnostic range what is the wavelength range of X-rays?

Answer 16

.1-.5 angstroms

Question 17

How does a motor work?

Answer 17

By sending an alternating current through a coil of wire that has been placed within a magnetic field. The alternating current through the coil produces a fluctuating magnetic field which is repelled and attracted by the stationary magnetic field causing the motor to spin.

Question 18

What determines the strength of a magnetic field?

Answer 18

The number of flux lines in an area

Question 19

What formula is used to find how many electrons will fit within a given shell of an atoms?

Answer 19

2 x n-squared

Question 20

What is a device whose electrical resistance may vary called? What does it do?

Answer 20

A rheostat

Controls the amount of current in a switch

Question 21

On a spinning top, how many dots would show during a one second full wave rectified exposure?

Answer 21

120, one for each impulse

Question 22

If the voltage is stepped up, what happens to the current in the secondary side of the transformer?

Answer 22

Decreases

Question 23

A material that disallows the flow of electrons is known as what?

Answer 23

Insulator

Question 24

Name the electromagnetic waves from the shortest to longest wavelengths.

Answer 24

Xray, ultraviolet, visible light, radar TIP: The shorter the wavelength the higher the energy

Question 25

What type of current is supplied by a battery?

Answer 25

Direct

Question 26

What are materials called that are weakly attracted to a magnet?

Answer 26

Paramagnetic

Question 27

An excessive amount of electrons at one end of a conductor and a deficiency at the other is known as what!? Explain

Answer 27

Voltage The potential difference between the two ends of a conductor determines how much force will be applied to the electrons in the conductor. This pushing and pulling force is called voltage.

Question 28

Who is given credit for describing what an atom looks like?

Answer 28

Neils Bohr

Question 29

What will create the most resistance? A) long wire small diameter B) short wire small diameter C) long wire large diameter D) short wire large diameter

Answer 29

A) long wire snake diameter

Question 30

What is the device that measures electrical current called?

Answer 30

Ammeter

Question 31

What is the unit of capacitance? Define it and it's equation for measurement

Answer 31

Farad The amount of charge per volt that can be stored on metal plate C(capacitance in farads)=q(charge)/V

Question 32

What is the unit for resistance?

Answer 32

Ohm Represents the characteristics of a material that inhibits the flow of electrons

Question 33

What is constant throughout a series circuit?

Answer 33

Amperage

Question 34

What is the unit of electrical power?

Answer 34

Watt

Question 35

What type of bond holds atoms together by sharing their outer electrons?

Answer 35

Covalent

Question 36

What is a device that stores electrical charges called?

Answer 36

Capacitor

Question 37

What is the unit of electrical charge?

Answer 37

Coulomb

Question 38

What is power and it's equation?

Answer 38

The rate at which work is done P=work/time

Question 39

What is the prefix for one million?

Answer 39

Mega

Question 40

What is the unit of force?

Answer 40

Newton

Question 41

What is the formula for ohms law?

Answer 41

V=IR Voltage=amperage x resistance

Question 42

What is the unit of electrical current?

Answer 42

Amperage

Question 43

What is the formula for voltage?

Answer 43

V=W/Q Voltage=joule/coulomb

Question 44

What unit measures work done on a charged particle?

Answer 44

Volt

Question 45

What type of generator has a voltage ripple of less than 1%?

Answer 45

High frequency generators

Question 46

What type of motor drives the rotating anode? Why is it called that?

Answer 46

An induction motor. The stator is on the outside of the glass tube and it induces the rotor on the inside of the tube to spin.

Question 47

What type of current is indicated by the milliammeter?

Answer 47

Tube current

Question 48

What type of current supplies the X-ray tube?

Answer 48

Pulsating direct current

Question 49

What conversion occurs in the image at the output phosphor of an image intensifier tube?

Answer 49

Electrons are converted to visible light

Question 50

Where is the xray circuit is the timer located?

Answer 50

Between the auto transformer and the step up transformer

Question 51

Why are high frequency generators more efficient at producing X-rays than single phase generators?

Answer 51

Voltage never drops to zero so there is a continuous production of X-rays