What happens to area if diameter is doubled?

What happens to area if diameter is doubled?

1 Answer. Daniel L. If the diameter of a circle is doubled, its area increases 4 times.

Is radius double the diameter?

The diameter measures how wide the circle is, and is always equal to twice the radius (2r).

Is the radius of a circle double the diameter?

Thus the diameter of a circle is twice the radius of that circle. A diameter divides the circle into two congruent parts. Each part is called a semicircle. If we draw a radius perpendicular to the diameter in a semicircle, we obtain two congruent quadrants.

What happens to a circle as its radius increases?

The area of a circle is equal to the square of its radius times pi. The circumference of a circle is equal to the diameter times pi. So when you double the radius, the area goes up by 4 times because 2 squared is 4. The area will always go up by the square of how much the radius goes up.

How fast will the circumference of a circle increase when the radius increases?

Example 2.1 The radius of a circle is increasing at a rate of 3 cm/sec. How fast is the circumference of the circle changing? constant. As the radius is increasing at a constant speed, the circumference is increasing at also a constant speed.

What happens to resistance when radius is doubled?

(b) Resistance of a wire is inversely proportional to the area of cross-section the wire. Thus, if radius is doubled, area increases four times and hence the resistance becomes one-fourth.

What is the resistance when both length and radius of the wire are doubled?

According to the question, the radius of the wire is doubled. Thus, the answer is (B). Note: We found the answer to be one-fourth as per this particular situation. But if the situation was to double the length, then the new resistance becomes four times of the original resistance.

What will be effect on specific resistance of radius of copper wire is doubled?

No. It won’t change. Specific resistance (also called as resistivity) is specific to material of the wire. It is independent of dimensions of wire.

When the radius of a copper wire is doubled?

Assertion: When the radius of a copper wire is doubled, its specific resistance gets increased. Reason: Specific resistance is independent of cross-section of material used. Step by step solution by experts to help you in doubt clearance & scoring excellent marks in exams.

Why is the resistance wire doubled before winding over the bobbin?

The resistance coils are double would to avoid induction effects Magnetic field deu to current in one half of the coil is cancelled by magnetic field due to current in the other half of the coil (which is in opposite direction).

Why wire is double folded in resistance box?

Generally wires in the resistance box are double folded and then coiled to nullify inductance effect. Because of this Magnetic induction caused by one half of the wire is cancelled by the magnetic induction caused by other half of the wire and keeping the wires with pure resistance.

How is the resistance coils placed inside the resistance box?

In resistance box, the resistor is fixed inside the box. They are arranged in such a manner that the value of resistance varies at every step. The box consists the rotary selector switch. The variable resistances are obtained by rotating the selector switches.

How are the various resistance coils connected in a resistance box?

one coil bridges each gap. The external circuit is connected at the terminal binding screws, and when all the plugs are in, the only resistance is that of the brass blocks and plugs themselves.

What is the arrangement for infinite resistance in a resistance box?

When infinity plug is taken out, air gap is introduced in the circuit. Since air is a bad conductor of current, no current flows in the circuit which implies resistance of infinity resistance is introduced in the circuit.

How do you test a resistance box?

Use to verify or calibrate a simple ohmmeter or multimeter If your resistance box has a high accuracy rating, you can use it to calibrate an ohmmeter or the resistance range of a multimeter. The setup is very simple, it is a direct connection of the resistance box to the port or probe of an ohmmeter or multimeter.

Why are the resistance used in a resistance box is like?

Why are the resistances used in a resistance box is like 1,2,2,5,10,20,20,50, etc. The combination of the resistances like 1,2,2,5,10,20,20,50 ohms gives any value of resistance. Hence, the above values are preferred on the resistance box to obtain any desired value.

What is INF in resistance box?

An infinite plug (INF) is also provided for convenience of users. Fitted in nicely polished teak wood box. Accuracy ± 0.02% to ± 0.05%. This listing is for 1 to 10000 ohms resistance box with 17 coils and 18 plugs Total resistance 21110 Ohms.

What is the use of resistance box in potentiometer?

What is the use of High Resistance box in meter bridge and potentiometer? The use of high resistance box is to minimize the current drawn from the cell so that internal resistance and emf of a cell can be measured.

What is the difference between resistance box and rheostat?

A resistance box is composed of a series of ten-position rotary switches with attached precision resistors. A rheostat is a variable resistor. Rheostats are usually made for high-current circuitry. They have two terminals (places to connect to).

What is a decade resistance box used for?

Decade boxes are ideal for troubleshooting circuits and verifying the accuracy of test equipment, both in the field and in the lab. Decade boxes are test instruments which use a series of resistors, capacitors, or inductors to simulate very specific electrical values.

What is a rheostat and what is it used for?

Rheostat, adjustable resistor used in applications that require the adjustment of current or the varying of resistance in an electric circuit. The rheostat can adjust generator characteristics, dim lights, and start or control the speed of motors.

What is the principle of post office box?

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.

Why it is called post office box?

The box containing Wheatstone bridge was used in the United Kingdom by engineers in General Post Office, who used it in UK telecommunications to trace electrical faults. Therefore, for historical reasons it was named “Post office box” as it was carried by post office engineers.

How do you calculate resistance using a PO box?

Measurement of an unknown resistance using a Post Office Box R = R0 + 1 (ohm) are the resistance in rheostat arm, for which the deflection in galvanometer is in opposite direction, then it implies that the unknown resistance ‘s’ lies between R0 & (R0 + 1) ohm.