MasteringPhysics: Homework o3 Google Chrome https://session.masteringphysics.com
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MasteringPhysics: Homework o3 Google Chrome https://session.masteringphysics.com/myct/itemView?assignmentProblemID D*62249032 PHYS 40C, Spring 2016 Homework 03 Problem 28.46 Problem 28.46 Part A In proton-beam therapy, a high-energy beam of protons is fired at a tumor. As the protons stop in What is the total charge ofthe protons that must be fired at the tumor? the tumor, their kinetic energy breaks apart the tumors DNA, thus killing the tumor cells. For one Express your answer totwo significant figures and include the appropriate units. patient, it is desired to deposit 0.12 J of proton energy in the tumor. To create the proton beam, protons are accelerated from rest through a 1.1x104 kvpotential dimerence. 10 nc Submit My Answers Give Up incorrect; Try Again; 5 attempts remaining O Ask me anything Signed in as Kurt Tomongin I Hele I cose Resources previous l 11 of 14 I neod. Continue 1:32 PM 4/19/2016Explanation / Answer
The unit of charge q is coulombs.
One coulomb has 6.242×10^18 proton equivalents of charge.
http://en.wikipedia.org/wiki/Coulomb
One volt is one joule per coulomb,
so one joule is gained when one coulomb passes through one volt.
Energy = Coulombs * Volts; E = q*V
q = E/V = 0.12J / 11 MV = 10.9*10^-9 C = 10.9 nC