Question

A) A proton is placed at point A, where the electric potential is 100 V . The proton is released from rest. Some time later, the proton has reached point B, where the electric potential is -140 V . What is the de Broglie wavelength of the proton when it reaches point B?

_____ m

B) We then place an electron at point B and release it from rest. What is its de Broglie wavelength when it reaches point A?

_____ m

Answer 1

Pat (A) P Petentiol at poisal A. Potedial at point B, Vo-14 V Patential dilerene V2 lo0-140) V V2240V de Breglie wovelength is giun by h 2me V (A) Far Praton where CPlan ks tnstent) mp6711 e 16110-14 -97 Cmess af pa ton) Кg Cchaage of proton) 661 10-34 2x1.67 xl6x L6 Xl0" X 240 6.611-34 a J12 82.56 Xl-e 6.6Y-35 35.8 A-28 2 1.84 Ylo m For Electean (B) 2 meV

Date V24a V wheer 39 Is CPlank's Costand) (mass of electaon) Ctharge eletn 9-1X l 16 x-14 me e 6.6 X10 29.133' 1.6 x) 24 -3 -35 6.6%J -2S 83. 54 10 -0 2 7.89 Xlo