How does post office box Work physics?
It works on the principle of Wheatstone bridge to identify the resistance of wire connected and then by using wire resistivity and cross section calculating length of wire and thus determining where the cable had broken.
Physicists named the post office box because it is fabricated to find the resistance of electric cables and telegraph wires(telecommunication purposes), also used by post offices to figure out the resistance of the transmission lines laid for communication objectives.
What is the aim of the post office box experiment?
Post Office Box is helpful in physics experiment to determine the unknown resistance of wires like Constantan and Nichrome etc. With the help of Nvis 6041, the student can learn the principle of Post Office Box and its working. It can determine the specific resistance of different types of wire.
The best material for resistance in post box resistor is Manganin. It is an alloy of copper (85%), Manganese (12%) and Nickel (2%).
What is the formula of post office box?
S=QPR.
A Post Office Box is used to measure an unknown resistance. It is basically a Wheatstone bridge with three arms known as P, Q, and R; while the fourth arm is the unknown resistance, denoted by S. P and Q are called the ratio arms while R is called the rheostat arm.
What is measured by using post office box?
an unknown resistance
What is the Wheatstone Bridge Principle? The Wheatstone bridge works on the principle of null deflection, i.e. the ratio of their resistances is equal, and no current flows through the circuit. Under normal conditions, the bridge is in an unbalanced condition where current flows through the galvanometer.
What is the practical utility of the post office box in day to day life?
Answer: By post office we can get our e mail and neccessary things and we can also parcel neccessay information in form of letters, envelops and post cards etc. and then we can give it in an post office with name and address of that person and in few time the postman will deliver it to the address written on it.30-Jul-2020
Electrical. Resistance is a measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms, symbolized by the Greek letter omega (Ω). Ohms are named after Georg Simon Ohm (1784-1854), a German physicist who studied the relationship between voltage, current and resistance.
What is a resistance box?
Definition of resistance box : an instrument for measuring and comparing electrical resistances.
This reduces the volume of the letterbox, thus reducing the cost of transportation. This also helps in protecting the plastic top during transit. India Post now plans to replace the old letter boxes with the new ones wherever necessary.
How do I turn in my PO Box key?
If you want to receive back your PO Box key deposit, you can head to the post office where your rental resides and tell the postal service representative that you'd like to cancel the service. Be prepared with your PO Box keys and number handy.30-Mar-2020
A meter bridge is an electrical apparatus that is used to measuring the unknown resistance of a conductor. It consists of a wire of length one meter. Hence it is called a meter bridge.26-Sept-2021
Why is Wheatstone bridge so called?
Instead the apparatus, composed of four resistors, a battery and a galvanometer, was named for the man who popularized it — Sir Charles Wheatstone. A scientist and mathematician, Samuel Hunter Christie, developed the circuit to measure unknown electrical resistances and first described it in 1833.10-Dec-2014
A Wheatstone's bridge is more accurate than the other methods of measuring resistance because the resistance is obtained using the null method and is based on Kirchoff's law. In the null method, the resistance of the galvanometer and the internal resistance of the cell does not affect the null point.
What are uses of post office?
The primary function of Post Office is collection, processing, transmission and delivery of mail.
Beat Number. The two digit number additional to PIN to be used by Postal Dept. for sorting the mail. It is an instance of Postal Service G02.
Why do we need a post office for Class 2?
Explanation: In most of the regions in India, people live in backward areas where technology is not present. People communicate with each other and send and receive documents through traditional methods. That's why a post office is necessary for the neighborhood so people can send and science messages and letters.10-Apr-2020
Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it, provided all physical conditions and temperatures remain constant. In the equation, the constant of proportionality, R, is called Resistance and has units of ohms, with the symbol Ω.
Does higher resistance mean higher voltage?
Ohm's law states that current is directly proportional to voltage but inversely proportional to resistance. At constant resistance, current increases as voltage increases and vice versa. At constant voltage, current decreases as resistance increases and vice versa.06-Feb-2022
How does post office box Work physics?