fill the blanks -7
Charges of the same polarity repel each other, while unlike charges experience a strong … force
attractive
If a glass rod is rubbed with silk, some of the electrons are removed from the rod and it then has a net … charge.
positive
The gravitational force inside an atom is …. compared to the electrostatic force.
negligible
Metals are said to be good …. of electricity because of the availability of charge carriers.
conductors
The quantum of charge is the … unit of charge that can be isolated
smallest
Protons and neutrons are made up of smaller charged particles called…... .
quarks
A simple device called … is composed of a metal rod with two strips of very thin metal foil attached to the bottom.
electroscope
The … through a wire is a measure of the amount of charge which passes through it per second
electric current
If an electroscope is uncharged, the two foil strips will … .
hang loosely
The unit of electric current is the ampere, which is defined as one...… per second.
coulomb
The electric field that exists around charged objects can be graphically represented by …
lines of force
A point charge is basically a concentration of charge at …. with no dimensions
mathematical point
A set of parallel plates, one with an excess positive charge and the other with an excess negative charge, seperated by an insulating material is referred to as a .…
capacitor
The unit of capacitance is the coulomb/volt, which is called a …
Farad
The electron beam in oscilloscopes is called a …… because it originates from the cathode.
cathode ray
Only few materials are attracted by magnets. These materials exhibit the property of “ … “ or „iron-like“ magnetism.
ferromagnetism
All materials can be classified in terms of their magnetic behavior as ferromagnetic, paramagnetic or …
diamagnetic
Electricity and magnetism are manifestations of the same force, the..… force
electromagnetic
In electric current meters, a coil of wire is placed so that it can rotate in the field of a … .
magnet
In electric current meters, the torque on the coil is proportional to the amount of … flowing in the coil.
current
The product of the magnetic field and the area is defined as the …. .
magnetic flux
The negative sign in Faraday ́s law indicates that the induced magnetic field always … the change that created it.
opposes
The relationship V=-N*dFi/dt is known as … law, where V is … , N is … and Fi is … .
Faraday's; voltage; number of coil; magnetic flux
The universal law of gravitation is a(n) … law since the gravitational force is inversely proportional to the square of the separation distance.
inverse square
The electric potential is defined as … per unit charge.
electric potential energy
The process of … a capacitor releases energy
discharging
The direction of the magnetic field vector associated with any current may be found by the … rule.
right hand
For practical purposes, electromagnets are prepared by adding … to the solenoid
iron core
The force exerted upon an electric charge by a magnetic field can be calculated by the equation …, where … .
F=qvB; q=positive charge; v=velocity; B=magnetic field
An important clinical application of .... is for the riliable monitoring of trace elements such as lead or arsenic.
spectometer