Cathode Rays

Quiz about the Australian HSC Yr 12 Topic Cathode Rays
Quiz by Timtam
Rate:
Last updated: July 10, 2018
First submittedJuly 9, 2018
Times taken4
Average score60.0%
Report this quizReport
12:00
Enter answer here
0
 / 35 guessed
The quiz is paused. You have remaining.
Scoring
You scored / = %
This beats or equals % of test takers also scored 100%
The average score is
Your high score is
Your fastest time is
Keep scrolling down for answers and more stats ...
Question
Answer
Plucker placed what on each end of a glass vacuum tube?
Metal Plates
What were these called?
Electrodes
What was created when the ^ where connected to an external high-voltage source?
An Electric Current
Which electrode glowed?
Anode
What was the charge of that electrode?
Positive
What electrode did the glow originate from?
Cathode
What colour did it glow?
Pale green
What did the Maltese Cross experiment identify about cathode rays
They travel in straight lines
What did the paddle wheel experiment identify about cathode rays?
They have momentum and therefore mass
What was concluded about cathode rays when magnets were placed on each side of the tube?
They are negative
He found this using the combined equation q/m=
v/Br
What actually are Cathode rays made up of?
Electrons
What was initially the conclusion obtained from placing electric plates on each side of the tube?
They have no charge
At lower pressures, what can electrons do in cathode ray tubes?
Accelerate to faster speeds
The first effect that can be seen in cathode ray tubes is?
glow discharge
The positive column is broken into what as pressure decreases?
Striations
These are separated by?
dark spaces
The colours of the discharge depend on what?
gas used
Name a gas used when using cathode tubes for lighting?
Neon or Mercury
What equation do you use to calculate the electrical field intensity using force and charge?
E=F/q
Electric field strength is calculated using the formulae:
E=V/d
Since W=Fd, then W also equals:
qEd or qV
What is work done equal to?
gain in energy
Since this is equivalent to kinetic energy, W=
1/2mv^2
J.J. Thomson finally proved a hypothesis regarding the actual effect of electric fields on cathode rays. What was the real electric charge of cathode rays?
negative
What equation calculates the force experienced by a particle in a magnetic field when the magnetic field is perpendicular to the particle's velocity?
F=qBv
If they are not perpendicular, what is the RHS of the equation multiplied by?
sine of the angle
J.J. Thomson used what to create uniform magnetic and electric fields?
charged parallel plates
By equating the magnetic and electric force equations when the beam was undeflected, Thomson was able to determine what?
velocity of the cathode ray particles
The electrons undergo what motion due to the magnetic field?
Circular motion
This meant that when the radius of the path was calculated, Thomson could obtain what?
charge to mass ratio
Why weren't scientists initially able to see the deflection in electric fields?
Pressure too high
What effect explains the emission of electrons from the cathode surface?
Photoelectric effect
List the two main uses of cathode ray tubes
Monitors
Cathode Ray Oscilloscopes
No comments yet