BackA uniform electric field exists in the region between two oppositely charged plane parallel plates. A proton is released from rest at the surface of the positively charged plate and strikes the surface of the opposite plate, cm distant from the first, in a time interval of s. Find the magnitude of the electric field.
Which of the following is a similarity between lectric fields and agnetic fields?
A proton is fired horizontally into a 1.0×105 N/C vertical electric field. It rises 1.0 cm vertically after having traveled 5.0 cm horizontally. What was the proton's initial speed?
A problem of practical interest is to make a beam of electrons turn a 90° corner. This can be done with the parallel-plate capacitor shown in FIGURE P23.55. An electron with kinetic energy 3.0×10−17 J enters through a small hole in the bottom plate of the capacitor. Should the bottom plate be charged positive or negative relative to the top plate if you want the electron to turn to the right? Explain.
A uniform electric field exists in the region between two oppositely charged plane parallel plates. A proton is released from rest at the surface of the positively charged plate and strikes the surface of the opposite plate, cm distant from the first, in a time interval of s. Find the speed of the proton when it strikes the negatively charged plate.
Air 'breaks down' when the electric field strength reaches 3.0×106 N/C, causing a spark. A parallel-plate capacitor is made from two 4.0 cm×4.0 cm electrodes. How many electrons must be transferred from one electrode to the other to create a spark between the electrodes?
The two parallel plates in FIGURE P23.53 are 2.0 cm apart and the electric field strength between them is 1.0×104 N/C. An electron is launched at a 45° angle from the positive plate. What is the maximum initial speed v0 the electron can have without hitting the negative plate?
Two large, parallel conducting plates carrying opposite charges of equal magnitude are separated by cm. If the surface charge density for each plate has magnitude nC/m2, what is the magnitude of in the region between the plates?
A 0.80-μm-diameter oil droplet is observed between two parallel electrodes spaced 11 mm apart. The droplet hangs motionless if the upper electrode is 20 V more positive than the lower electrode. The density of the oil is 885 kg/m3. Does the droplet have a surplus or a deficit of electrons? How many?
Electrostatic cleaners remove small dust particles and pollen grains from air by first ionizing them, then flowing the air between the plates of a parallel-plate capacitor, parallel to the plates, where electric forces deposit charged particles on one of the electrodes. A typical pollen grain has a mass of g, the ionizer charges it with extra electrons, and a fan moves the air at m/s. Ignore air resistance and gravity. What minimum electric field strength is needed to deflect the grain by mm before it leaves the electrodes?
Two 2.0-cm-diameter disks face each other, 1.0 mm apart. They are charged to ±10 nC. A proton is shot from the negative disk toward the positive disk. What launch speed must the proton have to just barely reach the positive disk?
A proton is traveling horizontally to the right at m/s. How much time does it take the proton to stop after entering the field?
FIGURE EX23.25 shows a g ball hanging from a string inside a parallel-plate capacitor made with 12 cm × 12 cm electrodes. The electrodes are charged to±75 nC. What is the charge on the ball in nC?
An electron moves into a capacitor at an initial speed of 150 m/s. If the electron enters exactly halfway between the plates, how far will the electron move horizontally before it strikes one of the plates? Which plate will it strike?