test bank questions
What voltage would produce a current of 100 amps through an aluminum wire which has a resistance of 3.44 ohms ?
344 Volts
According to Ohm's Law, what would the current be if the resistance is 1.5 Ohms and the voltage is 12 Volts?
8A
Chemical Energy Examples:
: Food, Battery, Burning candle or Wood, Fireworks, Fossil Fuels, Gasoline
If an AC source in a circuit produces 40V, and the resistor has a value of 20 Ω. What is the current?
2A
Objects cannot be electrified by induction
False
What type of energy cooks food in a microwave oven?
RADIANT ENERGY
Good Conductors have low resistance : .
True
how is Potential Energy Converted to Kinetic Energy ?
When stored energy begins to move, the object now transfers from potential energy into kinetic energy
Electromagnetic energy cannot travel through a vacuum. true or false
false
T/F the velocity of EM energy is equal to the speed of sound
false it is equal to the speed of light.
true/false Induction is a process of electrical fields acting on one another with direct contact
false (with out)
all circuit elements are connected in a line
series
Light behaves as both a _____and ______
particle and wave
Ohms
resistance
known as a variable resistor
rheostat
A ball is dropped from the top of a building. When is its potential energy the greatest?
right before it is dropped
T/F x-ray is a form of electromagnetic radiation
true
ice-cream melting gains thermal energy
true
insulator offer very large resistance to the flow of electrical current true/false
true
true or false As the length of the conductor increases, the resistance increase
true
true/ false All electromagnetic radiation travels at the same speed
true
true/ false for potential difference to exist, there must be electron flow
true
true/false If any part of a series circuit is broken , the circuit fails
true
true/false Lightening is a huge build up of static electricity in the clouds
true
true/false Objects can be electrified by induction
true
What is the formula for the conservation of mechanical energy?
(KE + PE) beginning = (KE + PE) end Mechanical energy is the sum of the potential and kinetic energies in a system. The principle of the conservation of mechanical energy states that the total mechanical energy in a system (i.e., the sum of the potential plus kinetic energies) remains constant as long as the only forces acting are conservative forces.
Electric current is which of these?
Flow of electrons, measured in amperes
Friction
Rubbing two objects together can cause electrons to be "wiped" from one object and transferred to the other
Mass
SI - kilogram, kg Defined in terms of a kilogram, based on a specific cylinder kept at the International Bureau of Standards
Potential Energy (PE)
STORED energy or Energy that is NOT being used
What is the voltage if a circuit has a resistance of 4 ohms (Ω) and a current of 6 A?
24 V
electrical energy
Electricity flows in a closed path to form a circuit, and stops when the circuit is broken Conductors-copper, aluminum, and steel Insulators- rubber, plastic, glass, wood, and cloth
Electrostatics
Electrostatics is the study of fixed or stationary electric charge
X-rays and Light rays have the same : Velocity Wavelength energy intensity Frequency
Velocity
which affects kinetic energy more? Mass or Velocity and why
Velocity has more of an affect on kinetic energy because the velocity is squared.
energy contained within a system that is responsible for its temperature
heat
the energy acquired by the object upon which work is done is known as
heat
Radio waves are used in
magnetic resonance imaging
The amount of matter in an object
mass
Ice and steam are examples of two forms of
matter
The energy acquired by the objects upon which work is done is known as ___________
mechanical
energy contained within a system that is responsible for its temperature.
mechanical
The SI unit of length
meter
Forms of Kinetic Energy
sound waves, thermal energy (heat), the electromagnetic (light waves), electricity
Interaction of Light and Matter
-Emission • Absorption • Transmission (passing through) • Reflection (scattering)
An object moving with a speed of 21m/s and has a kinetic energy of 140J. What is the mass of the object : 0.63kg 1.98Kg 1.28kg 3.48kg 16.87kg
0.63kg
an object moving with a speed of 21 m/s and has a kinetic energy of 140 j. what is the mass of the object
0.63kg
the total distance in a circuit is 9 ohms and the total voltage is 3 volts what is it's current
1/3 ampere.
What voltage produces a current of 50 amps with a resistance of 20 ohms ?
1000 Volts
How much voltage gives 5 amps of current through a 3 ohm light bulb
15 v
A MP3 player uses a standard 1.5 V battery. How much resistance is in the circuit if it uses a current of 0.010A:
150 ohms
a current of 2 amepers and a resistance of 8 ohms require what voltage in a circuit
16v
the ampere is defined as _______ coulomb passing by a point is____ second
1:1
The ampere is defined as ______ coulomb passing by a point in ____ second.
1; 1
What voltage produces a current of 500 amps with a resistance of 50 ohms?
25,000 Volts
An object moving with a speed of 35m/s and has a kinetic energy of 1500J, what is the mass of the object: 2.45kg 1.28kg 3.48kg 16.87kg
2.45kg
an object moving with a speed of 35 m/s and has a kinetic energy of 15000 J what is the mass of the object.
24.5kg
A filament bulb has a current of 0.2 A running through it, with a potential difference of 5V across it. What is the resistance of the filament in the bulb
25 Ω
If a person riding a bike has a mass of 200 Kg and is moving at a velocity of 5 m/s , what is its Kinetic Energy: 2500J 10J 500J 2J 20J
2500J
if a person riding a bike has mass of 200 kg and is moving at a velocity of 5 m/s what is its kinetic energy.
2500j
A kitchen toaster draws 0.5 A through a conductor that has a resistance of 6 Ohms. What is the voltage across the conductor?
3 V
An electric circuit has a current of 3 amperes and a resistance of 2 ohms. What is the current if you increase the total resistance in the circuit to 6 ohms? (Assume that the voltage is unchanged.)
3 amperes
Find the voltage in an extension cord having a 6.600 Ω resistance and through which a 5.00A current is flowing:
33.0V
A current of 250 amps is flowing through a copper wire with a resistance of 2.09 ohms. What is the voltage?
522.5 Volts
What current flow through a hairdryer plugged into a 110v circuit if it has a resistance of 25 ohms
4.4a
An x-ray unit draws a current of 220.5 A. If the voltage is 1000 V what is the electrical resistance of the unit :
4.5 ohms
A kitchen toaster draws a current of 2.5 A. If the household voltage is 110 V, What is the electric resistance of the toaster?
44 Ohms
What is the voltage in a circuit of 100 amperes and 5 ohms
500 V
what is the voltage in a circuit if the current is 200a and the resistance is 3 O
600 v
What is the voltage in a circuit if the current is 200A and the resistance is 3 Ω?
600V
The overall resistance of a mobile x-ray imaging system is 12 Ω. When plugged into a 110 V receptacle, how much current does it draw?
9.2 A
the overall resistance of a mobile x-ray image is 12 O when plugged into a 110v receptacle how much current does it draw.
9.2 a
electromagnetic energy
A form of energy that travels through space as waves
chemical energy
A form of potential energy that is stored in chemical bonds between atoms.
How is a magnetic field produced?
A magnetic field is produced by the motion of electric charge.
States of Matter: Plasma
A plasma is an ionized gas. A plasma is a very good conductor of electricity and is affected by magnetic fields. Plasma's, like gases have an indefinite shape and an indefinite volume. plasma is the common state of matter Particles in Plasma Particles in Plasma
Which of the following is true of all electromagnetic energy? All are true It has no mass. It travels in waves. It moves at the speed of light.
All are true
What is the mechanical source of energy for electrical generators that supply electricity to our cities?
All of the answers are correct
What is the device called that measures the amount of electric current flowing through a circuit at a particular point?
Ammeter
The measurement of the height of an electromagnetic wave form the average to the maximum is called:
Amplitude
The refraction of light waves is seen in which of the following?
Bending of light waves by a prism
Identify the Energy Transformation
Chemical --->Mechanical
Chemical Energy
Chemical Energy is the potential energy stored in substances. Calories = the chemical energy of food Batteries also have chemical energy It all depends upon the position and arrangement of the atoms in a compound.
Please match the following terms with their meanings
Closed circuit
Name examples of conductors
Conductors Any material that allows electric charges to move through it Examples: Metals (esp. copper) Your body Electric wires Insulators Materials that do not allow electric charges to flow freely through them Examples: Wood Glass Rubber
Solids
Definite shape and volume Particles in Solids: Are packed tightly together Have very little energy Vibrate in place
Identify the Energy Transformation
Electrical ----> Heat (Thermal)
Which of the following is true?
Energy can be transformed from one form to another.
the law of conservation of energy Light
Energy cannot be created or destroyed. It can only be changed from one form to another
Electromagnetic Energy
Energy consisting of an electric field and magnetic field, perpendicular to each other, but traveling together through space
Light (Radiant) Energy
Energy created by vibrating particles that create waves that travel through space and time. [These waves are called electromagnetic waves.]
KINETIC ENERGY
Energy in MOTION or Energy that IS being used
light energy
Energy in the form of moving waves of light
Potential Energy
Energy of an object by virtue of its position
kinetic energy
Energy of an object by virtue of its speed K.E. = (1/2) X mv2 m= is mass v = velocity
Chemical Energy
Energy stored in chemical bonds When chemical bonds are broken, new chemicals are formed and some of it is released energy
Nuclear Energy
Energy stored in the nucleus of an atom
nuclear energy
Energy stored in the nucleus of an atom
Nuclear Power
Energy stored in the nucleus of an atom from fission or fusion
Electromagnetic Energy
Energy that travels in waves
If any part of a series circuit is broken, the circuit continues to work :
False
true/false According to the Law of Conservation, mechanical energy can never be converted to thermal energy, only electrical energy
False
true/flase the velocity of EM energy is 3x10-10 p cm/sec2
False all electromagnetic radiation travels at the same speed which is about 3.0 * 10-8 meters per second through a vacuum.
WORK is
Force exerted on an object that causes it to move
Resistance caused by one object moving against another
Friction
When electrons rub off one object and are deposited on another, this is said to be electrification by:
Friction
When your charged fingertip touches a metal doorknob and the charge is transferred to the door, this is done by: All the answers are correct Friction Induction Contact
Friction
At room temperature helium does not have a definite shape or volume . Which state is it in :
Gas
Gases
Gases spread out to fill the entire space given and do not have definite volume. Gases have mass. Gases take up space. Particles in Gases: Move freely Have LOTS of energy
Albert Einstein 1905
German physicist who developed the theory of relativity, which states that time, space, and mass are relative to each other and not fixed. He showed that if matter is destroyed, energy is created, and if energy is destroyed mass is created. 2 E = MC
Which of the following has the lowest frequency?
Infrared light
Something that does NOT allow thermal energy to pass easily
Insulator
SI unit for work and energy
Joule
What is the unit for Kinetic and Potential Energy ?
Joules
Mass without movement has no:
Kinetic energy
mechanical energy
Kinetic or potential energy associated with the motion or position of an object
List the three systems of measurement
Length, Mass and time
Identify the Energy Transformation
Light ---->Chemical
Liquids
Liquids take the shape of their container and have definite volume. Liquids have mass. Liquids take up space Particles in Liquids: Are loosely packed Have medium energy levels Particles flow around each other
When you plug an electric fan to a power outlet, electrical energy is transformed into what type of energy?
MECHANICAL ENERG
What type of energy is the spinning plate inside of a microwave oven?
MECHANICAL ENERGY
electromagnetic radiation causes both _____ and _____ disturbances.
Magnetic, electrical
Albert Einstein
Mass-Energy Equivalence Albert Einstein E=mc2 E = energy m= mass c= speed of light 3 x 108 m/s
Energy of motion The total energy of motion and position of an object (potential energy + kinetic energy
Mechanical Energy
What type of matter is classified as a conductor of thermal energy:
Metal
acceleration
Meters per second squared (m/s2) is the unit of measure of:
Thermal Energy Transfer
Movement of thermal energy from an area of high temperature to an area of low temperature
Electrical Energy
Moving electrical charges that produce electricity and energy.
X-rays were discovered:
November 8, 1895
Induction
Occurs when charges in an uncharged object are rearranged WITHOUT direct contact with the charged objec
What is the formula for gravitational potential energy?
PE = mgh
what is the formula for gravitational potential energy?
PE= mgh
There are two main kinds of energy
POTENTIAL ENERGY KINETIC ENERGY
How is all energy divided? Potential Energy Kinetic Energy All Energy?
Potential Energy a) gravitation potential energy. b) elastic potential energy c) chemical potential energy Kinetic Energy Kinetic Energy is the energy of motion or energy in use Any matter in motion has Kinetic Energy There are many forms of Kinetic Energy Some forms include: light (radiant), thermal (heat), sound (acoustic), electrical, and mechanical
gravitational potential energy
Potential energy that depends on the height of an object
Identify the electrical properties of subatomic particle
Protons (+) and electrons (-) are charged Objects can become charged when atoms in the objects gain or lose electrons.
An ohm is the SI unit for:
Resistance
on the surface of an electrified object , the charges concentrate
Sharpest curvatures.
Different types of energy
Some different types of energy are: Thermal energy Kinetic energy Gravitational potential energy Elastic potential energy Chemical energy Magnetic energy Electrostatic energy Nuclear energy
conductor
Something that allows thermal energy to pass easily Metal Water
sound energy
Sound energy is caused by an object's vibrations A vibrating object transmits energy through the air around it in waves (longitudinal waves)
The metric system is also known as the:
System International (SI)
Discuss the derivation of scientific system of measurement
The SI consists of base units and derived units: (1) The base units comprises an irreducible set of units for measuring all physical variables (2) The derived units can be expressed in terms of the base units
the flow of electrons along a conductor is:
The force required to make current flow through a conductor is called voltage and potential
Law of Conservation of Energy
The rule that energy cannot be created or destroyed
Energy conversions
The sun's energy through solar cells can be converted directly into electricity. Green plants convert the sun's energy (electromagnetic) into starches and sugars (chemical energy).
Increasing the resistance in the a circuit results in a?
This means that increasing the voltage will cause the current to increase, while increasing the resistance will cause the current to decrease.
Conduction
Transfer of electrons from one object to another THROUGH direct contact
Which of the following devices can increase or decrease voltage by a set amount?
Transformer
Insulators offer very large resistance to the flow of electrical current : True False
True
T/F as two electrical charges move farther apart the force between them decreases proportionally to the inverse square of their separation
True
Water is a good conductor:
True
Which of the following can cause skin cancer?
Ultraviolet light
Length
Units SI - meter, m Defined in terms of a meter - the distance traveled by light in a vacuum during a given time
The difference in the electric potential between two points is measured in:
Volts
Water is a good conductor of electricity.
Which of the following statements about water and electricity is MOST accurate? (170)
x-rays where discovered by
Wilhelm Roentgen, Professor of Physics in Wurzburg, Bavaria, discovered X-rays in 1895—accidentally—while testing whether cathode rays could pass through glass.
the first x-ray was
Wilhelm Roentgen, wife hand
Which of the following is the best electrical insulator? Wood Water Nickle Copper
Wood
a step-up transformer results in
a transformer that increases voltage The step-up transformer uses a process called mutual induction to convert low voltage into high voltage. Diodes are the main component within rectifiers
Ohms law can be written as : Volts = amps x ohms Ohms = volts x amps amps= volts x ohms all are correct
all are correct
If a conductor is curved, the greatest amount of charge will be found:
along the straightest area of thalong the straightest area of the conductor.e conductor.
Current that changes direction in the conductor is:
alternating current
electron oscillating back and forth
alternating current
When considering the wave properties of electromagnetic radiation, the maximum height of a wave is
amplitude
the measurement of the height of an electromagnetic wave form the average to the maximum is called.
amplitude
current that changes direction in the conductor is
at the area of the greatest curvature of the conductor
A device that temporarily stores charge is the:
capacitor
principles of non moving electric charges
electrostatic
a device that temporarily stores charge is the
capacitor
stores charges
capacitor
the study of stationary or resting electric charge is called
electrostatic's
the device that produces electrons through a chemical reaction is a
battery
the refraction of light waves in seen in which of the following?
bending of light waves by a prism
Joules
energy
electromagnetic, chemical, electrical and thermal are all types of:
energy
the ability to do work
energy
x-rays and light have the same
energy
Light travels with a speed of
c= 300,000 km/s
Energy stored in the bonds of chemical compounds and may be released during a reaction
chemical
energy stored in the bonds of chemical compounds and may released during a reaction
chemical
A way of drawing electrical circuits
closed circuit
what determines the state of matter?
energy amount of temperature and pressure
The direct transfer of heat from one object to another
conduction
A material that
conductor
any material that allows the free flow of electrons is called an
conductor
A unit used in measuring the amount of charge
coulomb
The unit of measurement of electrical charges (SI) is:
coulomb
the unit of measurement of electrical charge (si) is
coulomb
Force of attraction or repulsion inversely proportional to the square of distance
coulombs law
Amps
current
The flow of electricity through a circuit
current
Obtained by combining SI units
derived unit
In an electric fan the energy transformation that occurs is
electrical to mechanical
Caused by the flow of electrons
electricity
The study of electric charges in motion is:
electrodynamics
Light energy is an example of which form of energy?
electromagnetic
the energy of an x-ray is
electromagnetic
radio waves, light and x-rays are all examples of____ energy
electromagnetic energy
Different electromagnetic radiations are put in order by the:
electromagnetic spectrum
elastic potential energy
elastic potential energy is associated with objects that can be stretched or compressed. Elastic potential energy can be stored in rubber bands, bungee chords, trampolines, springs, an arrow drawn into a bow, etc.
A magnetic field is produced by
electric charges in motion.
A closed pathway of wires and related elements is a(n):
electric circuit
The ampere is the unit of measure for:
electric current
The flow of electrons along a conductor is:
electric potential
Energy that's stored in charged particles within an electric field__
electrical
energy thats stored in charged particles within an electric filed
electrical
Light (Radiant)
energy can be absorbed, transmitted, or reflected. • Includes energy from gamma rays, x-rays, ultraviolet rays, visible light, infrared rays, microwave and radio bands
Kinetic energy is best defined by which of the following?
energy of action/movement
heat energy (thermal energy)
energy that comes from internal vibration of atoms and molecules
The ______ is the number of peaks that pass by any point each second, measured in cycles per second or Hertz (Hz
frequency
the rate of rise and fall of a wave is called it's
frequency
which of the following can bemusement destroy cancer cells?
gamma waves
potential energy is at its ?
higher the object, the more potential energy.
The first radiograph produced by William Roentgen was of:
his wife's hand
Increasing the resistance in a circuit results in a (n)
increase in current
A step-up transformer results in:
increased voltage
the resistance in a wire decreases as it's diameter
increases
When there is movement of some of the electrons of an uncharged metallic object as it is brought into the electric field of a charged object, this is electrification by:
induction
A material that resists the flow of electricity
insulator
Photon wavelength is
inversely proportional to photon frequency
Electricity
is a form of energy that involves the movement of electrons from one point to another
physics
is the study of the basic components of the universe and their interactions. Theories of physics have to be verified by the experimental measurements.
The SI unit of mass
kilogram
mass without movement has no
kinetic energy
thermal energy (heat)
kinetic energy associated with the random movement of atoms or molecules
Five laws governing static electricity
laws of electrostatics
Body will remain at rest unless acted on by a force
laws of motion
During the process of freezing, a liquid
loses kinetic energy
During the process of freezing, a liquid
loses potential energy
an electronic current can be introduced in a coil of i wire if it is placed in an
moving magnetic field.
the formula E=MC2 is the basis for the theory that led to the development of
nuclear power
The only difference between x-rays and gamma rays is their
origin
Volts
potential difference
Watt is the unit of measure of:
power
Watts
power
A watt is a unit of measurement know as?
power/energy
Light is a form of energy _______ energy
radiative
The lowest energy range of the electromagnetic spectrum is _____.
radio waves
Which of the following electromagnetic radiations have the lowest energy level?
radio waves
Light is ____ when it bounces off of mirrors or shiny surfaces
reflected
One of the laws of electrostatics is that like charges ________ and unlike charges ___________.
repel; attract
Photons with the highest frequencies have the _____.
shortest wavelengths
A substance that has its own shape
solid
the four states of matter are
solids, liquids, gases, plasma
The movement of energy through waves
sound
the movement of energy through waves
sound
A prism split light into a ______ (rainbow of colors)
spectrum
A build up of charge on an object
static electricity
ENERGY is
the ability to do work
Energy
the ability to do work
Static Electricity
the build up of electrical charges on an object
kinetic energy
the energy an object has due to its motion
energy conversion
the process of changing energy from one form to another
A German School teacher found the relationship between current , voltage and resistance: true/flae
true
the speed at which an object is moving at a given instant in time
velocity
Microwaves heat up food because their energy causes the atoms and molecules to
vibrate
Microwaves heat up food because their energy causes the atoms and molecules to:
vibrate
Examples of Light (Radiant) Energy
visible light, x-rays, gamma rays, and radio waves
Pushes electricity through a circuit
voltage
The ______ is the distance between adjacent peaks of the electric or magnetic field
wavelength
Laws of motion and gravitation
were discovered by Isaac Newton
Electromagnetic Radiation
•EM sometimes act like particles, sometimes like waves