Physics Chapter 22/Prelecture
If you rub an inflated balloon against your hair and place the balloon against the wall it will stick to the wall, illustrating
charge polarization
The electrical force between charges is strongest when the charges are
close together
Two charges separated by one meter exert 1-N forces on each other. If the charges are pulled 3 meters apart, the force on each charge will be
.11N
Which molecule is an example of a common electric dipole?
A water molecule
How does the charge of one electron compare to that of another electron? How does it compare with the charge of a proton? How do the masses of protons and electrons compare?
All electrons have the same charge. Electron charge is equal and opposite to the proton charge. A proton has 1800 times the mass of an electron.
What is an electric dipole?
In an electric dipole, positive and negative charges are separated on opposite sides of an object.
Which part of an atom is positively charged, and which part is negatively charged?
The nucleus is positively charged and the electron cloud is negatively charged.
An electric field is basically _________.
a vector quantity
A common naturally-polarized bit of matter is
a water molecule
An electron and a proton
attract each other
Electric charge can be transferred from one conducting body to another ________
by both contact and closeness
It is said that electric charge is conserved, which means that electric charge
can be neither created nor destroyed.
The force that binds atoms together to form molecules is
electrical
The fundamental force underlying all chemical reactions is
electrical
Two protons attract each other gravitationally and repel each other electrically. The stronger of these two forces is
electrical
In an electrically neutral atom the number of protons in the nucleus is equal to the number of
electrons that surround the nucleus
It is said that electric charge is quantized, which means that the charge on an object
is a whole number multiple of the charge of one electron
A highly-charged party balloon is not dangerous when it _________.
little overall energy
Conducting materials are composed of atoms with
loose outer electrons
A postive ion has more
more protons than electrons
Rub electrons from your hair with a comb and the comb becomes
negatively charged
Coulomb's law is most similar to which of these laws?
newtons law of gravity
Before a thunder storm, clouds in the sky likely become
polarized
A main difference between gravitational and electric forces is that electrical forces
repel or attract
When we say charge is conserved, we mainly mean that charge can be ______
transferred without loss like money in a bank
Electric potential, unlike electric potential energy, is measured in units of _________.
volts
Most atoms normally have a net charge that is _________
zero
The electric field inside the dome of a highly-charged Van de Graaff generator is _________.
zero
The net charge on a polarized molecule is normally _________.
zero
The net charge on an energized capacitor is normally _________.
zero