Anelectron and a proton are detected in a cosmicray experiment, the first with kinetic energy 10 keV, and the secondwith 100 keV. Which is faster, the electron or the proton? Obtain theratio of their speeds. (electron mass = 9.11 × 10–31kg, proton mass = 1.67 × 10–27kg, 1 eV = 1.60 × 10–19J).
Anelectron and a proton are detected in a cosmicray experiment, the first with kinetic energy 10 keV, and the secondwith 100 keV. Which is faster, the electron or the proton? Obtain theratio of their speeds. (electron mass = 9.11 × 10–31kg, proton mass = 1.67 × 10–27kg, 1 eV = 1.60 × 10–19J).
Electronis faster; Ratio of speeds is 13.54 : 1
Massof the electron, me= 9.11 × 10–31kg
Massof the proton, mp= 1.67 × 10–27 kg
Kineticenergy of the electron, EKe= 10 keV = 104eV
=104 ×1.60 × 10–19
=1.60 × 10–15J
Kineticenergy of the proton, EKp= 100 keV = 105eV = 1.60 × 10–14J
Hence,the electron is moving faster than theproton.
The ratioof their speeds:
Electronis faster; Ratio of speeds is 13.54 : 1
Massof the electron, me= 9.11 × 10–31kg
Massof the proton, mp= 1.67 × 10–27 kg
Kineticenergy of the electron, EKe= 10 keV = 104eV
=104 ×1.60 × 10–19
=1.60 × 10–15J
Kineticenergy of the proton, EKp= 100 keV = 105eV = 1.60 × 10–14J
Hence,the electron is moving faster than theproton.
The ratioof their speeds:
