How much kinetic energy does an electron lose when it goes from point a to point b if the voltage difference between these two points is 50 V and is slowing it down? a. 50 eV b. 50 V c. 1.60 x 10^-19 V d. 1.60 x 10^-19 J  e. None of the above

(a) Find the potential difference VB required to stop an electron (called a slopping potential) moving with an initial speed of 2.85 107 m/s. (b) Would a proton traveling at the same speed require a greater or lesser magnitude potential difference? Explain. (c) Find a symbolic expression for the ratio of the proton stopping potential and the electron stopping potential, Vp/Ve. The answer should be in terms of the proton mass mp and electron mass me.

In nuclear fission. a nucleus splits roughly in half. (a) What is the potential 2.00 10-14 m from a fragment that has 46 protons in it? (b) What is the potential energy in MeV of a similarly charged fragment at this distance?

Unreasonable Results (a) What is the final speed of an electron accelerated from rest through a voltage of 25.0 MV by a negatively charged Van de Graaff terminal? (b) What is unreasonable about this result? (C) Which assumptions are responsible?

Figure P27.75 shows four capacitors with CA = 4.00 F, CB = 8.00 F. CC = 6.00 F. and CD = 5.00 F connected across points a and b, which have potential difference Vab = 12.0 V. a. What is the equivalent capacitance of the four capacitors? b. What is the charge on each of the four capacitors?

The electric field strength between two parallel conducting plates separated by 4.00 cm is 7.50 104 V/m. (a) What is the potential difference between the plates? (b) The plate with the lowest potential is taken to be at zero volts. What is the potential 1.00 cm from that plate (and 3.00 cm from the other)?

(a) Calculate the electric potential 0.250 cm from ail electron, (b) What is the electric potential difference between two points that are 0.250 cm and 0.750 cm from an electron? (c) How would the answers change if the electron were replaced with a proton?

(a) Will the electric field strength between two parallel conducting plates exceed the breakdown strength for air ( 3.0 106 V/m) if the plates are separated by 2.00 mm and a potential difference of 5.0 103 V is applied? (b) How close together can the plates be with this applied voltage?

Q06. A nerve cell fires with a frequency of 50 Hertz (50 firing each second). With each firing, 105 singly-charged potassium ions are ejected through the cell's membrane, across which exists a potential of 90 mV. At what rate must energy be supplied (how many Joules per second) to the nerve cell, in order for it to fire? a. 8'10-14 J/s b. 3'10-14 J/s c. 9ʻ10-13 J/s d. 7'10-14 J/s

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