Show:
Protons and Electrons
Charging up Objects
Coulombs Law
Electric Force
Misc
100
You have 5 Protons, 4 Electrons, and 5 Neutrons. What is the charge on this object? Proton : 1.6*10^-19 C Electron: - 1.6*10^-19 C Neutron: 0 C
- 1.6*10^-19 C Only one electron left
100
If the charge on an electroscopes foil leaves are both positive, what will happen?
The foil leaves will spread apart
100
there are two charged balloons, the charge on one is doubled. What happens to the Force
Doubles
100
There are two charged objects, one is positive and one is negative. Will these objects attract or repel?
Repel
100
In an atom, what is the sign of the charge for the proton, electron, and neutron?
proton: + electron: - neutron: none
200
Identify several substances that are good conductors of electricity, and several substances that are good insulators of electricity.
Good Conductors: Copper, Iron, Metal Good Insulators: Plastic, Rubber, Ceramic
200
You are able to charge an object by bringing it near, but never touching. What is this method called?
Induction
200
there are two charged balloons, the distance between them is cut in half. What happens to the Force?
4x
200
What is the charge in Coulomb's Law, ie Electric Force, analogous to in the Gravitational Force?
Mass
200
Order the following materials from good conductor to bad conductor? Rubber, Wet Skin, Silver
Silver, Wet Skin, Rubber
300
What moves between objects Protons, Electrons, or Neutrons
Electrons
300
How might you charge in object by the conduction Method?
Allow the objects to touch
300
there are two charged balloons, the charge on both is doubled. What happens to the force?
4x
300
How do we know the Electric Force is greater than Gravitational Force?
the constant of proportionality, k, is greater than the Gravitational constant G
300
Rubbing a piece of fur against a charged plastic rod results in the rabbit fur being charged. How was it charged?
What is Friction!
400
A student creates identical electrical charges on identical balloons by rubbing them with a wool cloth. The balloons repel each other. According to Coulomb's Law, what should the student do to increase the electrical force of repulsion between these balloons?
Increase the charge on one of the balloons. OR Decrease the distance between the balloons.
400
What is the difference between an insulator and a conductor
Conductor - electrons are free to move Insulator - electrons can not move
400
there are two charged balloons, one charge is increased by 3x the other by 2x. What happens to the Force?
6x
400
A piece of fur is rubbed against a plastic rod. The resulting charge on the fur is +8 microCoulombs. What charge does the rod acquire?
-8 microCoulombs.
400
What MOST ACCURATELY describes the process of charging by induction?
A charged rod is brought close to, but does not touch, an uncharged sphere
500
A conductor differs from an insulator in that a conductor ________. a. has an excess of protons b. has an excess of electrons c. can become charged and an insulator cannot d. has faster moving molecules e. does not have any neutrons to get in the way of electron flow f. none of these
F. A and B are characteristic of positive and negative objects. As for C, both insulators and conductors can be charged. As for D, this has nothing to do with the conductive properties of materials. As for E, neutrons are located in the nucleus and are "out of the way" of mobile electrons.
500
Two objects are being charged by friction, one is a conductor and one is an insulator. What charge does the insulating object have?
Negative
500
there are two charged balloons, one charge is increased by 2x and the distance is decreased by 1/4 x. How will the force change?
32x
500
A capacitor is a device that can store electric charges. In a common design, charge is conducted to non­touching parallel plates where it is stored for use later. In order to move a charge in and out of the capacitor plates they must be what type of material?
What is CONDUCTIVE MATERIAL!
500
When an oil tanker car has arrived at its destination, it prepares to empty its fuel into a reservoir or tank. Part of the preparation involves connecting the body of the tanker car with a metal wire to the ground. Suggest a reason for why is this done.
As fuel is pumped from the tanker car to a reservoir, charge can quickly build up as the fluid flows through the hoses. This static charge can create sparks capable of igniting the fuel. By connecting the body of the tanker car to the ground, the static charge can be transferred to the ground. A metal wire is used since metals are conductive and allow charge to flow through them.