Energetic particles, such as protons, can be detected with a silicon detector. When a particle strikes a thin piece of silicon, it creates a large number of free electrons by ionizing silicon atoms. The electrons flow to an electrode on the surface of the detector, and this current is then amplified and detected. In one experiment, each incident proton creates, on average, electrons; the electron current is amplified by a factor of ; and the experimenters record an amplified current of . How many protons are striking the detector per second?
The number of protons that are striking the detector per second is
Number of electrons
Amplified by a factor
In this case, is the number of protons falling per second.
An elementary charge of equals a proton current of .
This current will be measured by multiplying it by the silicon sheet multiplication factor (let it be ), then multiplying it by the amplification factor (let it be ).
As a consequence, it is obvious that protons will flow at a relatively high rate
Substitute the expression,
Hence, the number of protons that are striking the detector per second is
73. A -mm-diameter proton beam carries a total current of . The current density in the proton beam, which increases with distance from the center, is given by , where is the radius of the beam and is the current density at the edge.
a. How many protons per second are delivered by this proton beam?b. Determine the value of .
A sculptor has asked you to help electroplate gold onto a brass statue. You know that the charge carriers in the ionic solution are singly charged gold ions, and you've calculated that you must deposit of gold to reach the necessary thickness. How much current do you need, in , to plate the statue in hours?
94% of StudySmarter users get better grades.Sign up for free