maalsahil2

One summer day a group of students were jumping from a railroad bridge into the Snohomish River. They stepped off the bridge when they jumped, and they hit the water 1.5 seconds later. How high was the bridge?

5.0 m

8.0 m

9.5 m

11 m

A parallel-plate capacitor is formed of two 10 cm × 10 cm platesspaced 1.0 cm apart. The plates are charged to
±1.0 nC. An electron is shot through a very small hole in thepositive plate.
a. What is the slowest speed the electron can have if it is toreach the negative plate (Hint: set final speed
at negative plate equal to zero)?

A 18.0-V battery is connected to two parallel metal plates placedin a vacuum. An electron is accelerated from rest from the negativeplate toward the positive plate.

a) What kinetic energy does the electron have just as it reachesthe positive plate?


b) What is the speed of the electron just as it reaches thepositive plate?

Two facing surfaces of two large parallel conductingplatesseparated by 11.5 cm haveuniform surface charge densitiessuch that are equal in magnitudebut opposite in sign. Thedifference in potential between theplates is 600 V.

A uniform electric field of magnitude 370 N/C pointing in thepositive x-direction acts on an electron, which is initially atrest. The electron has moved 3.00 cm.
(a) What is the work done by the field on the electron? in J
(b) What is the change in potential energy associated with theelectron? in J
(c) What is the velocity of the electron? magnitude ________m/s,direction (+y,+x,-y,-x)

A proton is released from rest at x = -2.80 cm in a constantelectric field with magnitude 1.51 103 N/C, pointing in thepositive x-direction.
(a) Calculate the change in potential energy when the protonreaches x = 5.22 cm.
J

(b) An electron is now fired in the same direction from the sameposition. What is its change in electric potential energy if itreaches x = 12.30 cm?
J

(a) Describe the motion of a proton after it is released from restin a uniform electric field.

*The proton accelerates in the direction of the electricfield.
*The proton accelerates in the opposite direction of the electricfield.
*The proton accelerates perpendicular to the direction of theelectric field.
*The proton remains at rest.

(b) Describe the changes (if any) in its kinetic energy.

*Its kinetic energy increases.
*Its kinetic energy decreases.
*Its kinetic energy remains the same.

(c) Describe the changes (if any) in the electric potential energyof the proton–field system.

*The electric potential energy of the system increases.
*The electric potential energy of the system decreases.
*The electric potential energy of the system remains the same.

A proton is released from rest in a uniform electric field ofmagnitude 80000 V/m directed along the positive x axis. The protonundergoes a displacement of 0.2 m in the direction of the electricfield as shown.

What is the amount of kinetic energy gained after it has moved0.2 m. Answer in units of J. Please explain.

A uniform electric field has a magnitude 2.30 kV/m and points inthe +x direction.

which statement out of these four is true.

Problem 1
A positive point charge is placed in a region of space wherethereis an electric field. If the charge is released from rest itwillaccelerate in a direction where the electric potential is

If a negative charge is initially at rest in an electric field, will it move toward a region of higher potential or lower potential? What about a positive charge? How does the potential energy of the charge change in each instance?

Problem1.

A) Asmall negative charge is released from rest inan electric field.Will the charge move toward a region of

higher orlower potential energy? Will the chargemove toward a region ofhigher or lower voltage?

B) Inwhat direction, relative to the direction ofan electric field, isthe voltage constant?

C) Whatis the voltage difference between two places insideaconductor?

What is the difference between the terms electric potential and voltage? give an example.