Why glass is insulating ?

1 Answer

Answer :

Glass is insulating so that electricity cannot flow through the glass

Related questions

Description : Which of the following is the most widely used insulating material for steam carrying pipelines? (A) Ceramic fibre blanket (B) Glass wool and 85% magnesia (C) Vermiculite (D) Slag wool

Last Answer : (B) Glass wool and 85% magnesia

Description : Which of the following is the most widely used heat insulating material for pipelines carrying steam? (A) Tar dolomite bricks followed by asbestos (B) Fireclay refractory followed by aluminium sheet (C) Cotton followed by aluminium foil (D) 85% magnesia cement and glass wool

Last Answer : (D) 85% magnesia cement and glass wool

Description : Which insulation is best for insulating root cellar?

Last Answer : First, what part of the country are you in? In Utah (where I last saw a root cellar) had a dirt floor, so humidity from the ground could help keep the vegetables humidified. If you are ... but many enter from the outside. http://www.organicgardening.com/learn-and-grow/building-root-cellar-your-home

Description : Does anyone here keep ferrets? I have a question about winter insulating?

Last Answer : Can you bring them into your home or basement at all? How cold does it get during your winters? Here in Wis I’d need a shed or hen house type structure to thoroughly keep them warm enough. (Personally if I had any they’d be indoors)

Description : What is the effect of heat on insulating material ?

Last Answer : With increasing temperature, the resistance of almost all solid insulators except Avro decreases. When the temperature drops again, the resistance increases.

Description : Who uses screwdriver and a insulating tape?

Last Answer : It is a ELECTRICIAN

Description : What are the benefits of insulating with foam board?

Last Answer : Foam board is generally used for acoustic insulation. If you're doing something noisy such as playing band instruments in a residential area, the benefit is that the foam will let you do so without violating ... in the rest of the house. Some people put them in basements and practice with a band.

Description : Biological functions of lipids include (A) Source of energy (B) Insulating material (C) Maintenance of cellular integrity (D) All of these

Last Answer : Answer : D

Description : In multi stage compressor, the isothermal compression is achieved by A. Employing intercooler B. By constantly cooling the cylinder C. By running compressor at very slow speed D. By insulating the cylinder

Last Answer : ANSWER : C

Description : Which of the following statements, concerning the general maintenance of a brushless generator, is correct? A. Paint should be applied to insulating surfaces on an annual basis. B. Alcohol should be used to ... . D. Accessible generator parts should be wiped with a clean dry rag on a periodic basis.

Last Answer : Answer: D

Description : On electrical generators one of the bearings is isolated from the bedplate. This insulating block should not be painted and must be kept clean to ___________. A. protect operating personnel from shock ... the prime mover as it warms up D. eliminate shaft currents to prevent damaging the bearings

Last Answer : Answer: D

Description : If the bearings of an electrical generator are failing more frequently than expected and the lubricating oil is sludging then you should ______________. A. check the connections to the output leads B. ... replace the bearing with a sealed roller type D. replace the thrust bearing of the prime mover

Last Answer : Answer: B

Description : Routine maintenance of dry-type transformers should include ______________. A. preventing the entrance of water from broken pipe lines steam lines B. keeping protective surfaces and insulating bushings free of ... debris C. periodic testing of insulation resistance with a megger D. all of the above

Last Answer : Answer: D

Description : In addition to undercutting the mica, proper maintenance of a D.C. motor's commutator includes _______________. A. side-cutting the copper segments and insulating the slots B. coating the copper surface with light machine ... in an oven at a maximum of 95°C for not over 8 hours D. all of the above

Last Answer : Answer: A

Description : Temporary repairs to an open DC propulsion armature coil can be made by _____________. A. connecting the coil ends directly to a pair of negative brushes B. disconnecting coil ends, insulating ... C. grounding the coil ends and short circuiting the commutator bar D. removing the sparking brushes

Last Answer : Answer: B

Description : Proper storage battery maintenance includes ____________. A. keeping connections tight and casing surfaces clean B. making sure electrolyte level is below the separator plates C. insulating the terminals with naval jelly D. maintaining a high charging rate at all times

Last Answer : Answer: A

Description : Which of the following statements best describes the material known as varnished cambric? A. Felted asbestos sealed with varnish. B. Cotton cloth coated with insulating varnish. C. Rubber ... Paper impregnated with mineral oil, specially wrapped with nonmetallic tape, and coated with varnish.

Last Answer : Answer: B

Description : A circuit breaker differs from a fuse in that a circuit breaker _____________. A. melts and must be replaced B. is enclosed in a tube of insulating material with metal ferrules at each end C. gives no visual indication of having opened the circuit D. trips to break the circuit and may be reset

Last Answer : Answer: D

Description : Electrical leads and insulation on a motor should be painted with ____________. A. heat-resisting acrylic B. heat-resisting aluminum C. insulating varnish D. insulating white lead

Last Answer : Answer: C

Description : What is the Difference Between "Insulating", "Isolating", and "Shielded Winding" Transformers?

Last Answer : Insulating and Isolating transformers are identical. These terms are used to describe the isolation of the primary and secondary windings, or insulation between the two. A shielded winding transformer, ... are connected to each other electrically, are not of the insulating or isolating variety.

Description : The compound of silicon used as insulating material for electric motors/appliances is

Last Answer : silicone.

Description : Give reason: Silicones used as insulating materials.

Last Answer : Unlike common organic polymers, silicones do not catch fire. Hence they are used in fire proof suits and insulating material.

Description : The heat flux (from outside to inside) across an insulating wall with thermal conductivity, K = 0.04 W/m.°K and thickness 0.16m is 10 W/m2 . The temperature of the inside wall is - 5°C. The outside wall temperature is (A) 25°C (B) 30°C (C) 35°C (D) 40°C

Last Answer : (C) 35°C

Description : The critical radius of insulation for a spherical shell is (where, K = thermal conductivity of insulating material h0 = heat transfer coefficient at the outer surface) (A) K/h0 (B) 2K/h0 (C) h0 /K (D) h0 /2K

Last Answer : (B) 2K/h0

Description : Low thermal conductivity of heat insulating materials is due to its (A) Dense structure (B) High proportion of air space (C) High specific heat (D) None of these

Last Answer : (B) High proportion of air space

Description : What do you understand by tan delta for a insulating material?

Last Answer : Tan delta measurement is done to find the qualities of insulating material. Tan delta is angle between current due to surface leakage or current due to capacitance and the capacitive current. That is Tan δ = Ir / Ic. 

Description : What do you mean by term insulating resistance? How it is measured?

Last Answer : Insulating resistance: insulating resistance is the opposition offered by an insulating material to the flow of current (electrons) through it when an high potential is applied across it. Insulating resistance ... properly. Then rotate the megger at rated speed of 160 rpm and take the readings.

Description : What is the temperature coefficient of insulating materials?

Last Answer : Insulators are negative temperature coefficient materials.

Description : What is good dielectric break down value for insulating oil?

Last Answer : 60 kV.

Description : Consider the following four conditions (1 - 4) and select a correct pair of them as adaptations to environment in desert lizards. Conditions: 1. Burrowing in soil to escape high temperature. 2. Losing heat rapidly from the body during ... to thick fatty dermis. (a) 3, 4 (b) 1, 3 (c) 2, 4 (d) 1, 2

Last Answer : (b) 1, 3

Description : What is the major factor that makes coaxial cable less susceptible to noisethan twisted-pair cable? A) inner conductor B) diameterof cable C) outer conductor D) insulating material

Last Answer : outer conductor

Description : The current flowing through an insulating medium is called a) Conduction b) Convection c) Radiation d) Susceptibility

Last Answer : b) Convection

Description : A steam pipe is intended to be insulated with two layers of insulating materials of different thermal conductivities. For minimum heat transfer to take place (A) The better insulation material should be put just ... to which insulating material is to be put inside (i.e., just next to the pipe)

Last Answer : (A) The better insulation material should be put just next to pipe (i.e., inside)

Description : Dielectric (A) Is an electrical insulating material (B) Of low resistivity is preferred (C) Should have high thermal conductivity (D) Need not defy the corrosive action of chemicals

Last Answer : (A) Is an electrical insulating material

Description : A steam carrying pipeline is insulated with two layers of insulating materials with the inferior insulation material forming the inner part. If the two insulating layers are interchanged, the heat conducted ... ) Remain unaffected (D) May increase or decrease; depends on the thickness of each layer

Last Answer : Option C

Description : The low voltage porcelain is mainly used for (A) Switch block (B) Insulating tubes (C) Lamp sockets (D) All of these

Last Answer : Answer: Option D

Description : Carnot cycle efficiency depends upon  (a) properties of the medium/substance used  (b) condition of engine  (c) working condition  (d) temperature range of operation  (e) effectiveness of insulating material around the engine.

Last Answer : Answer : d

Description : The disadvantage with paper as insulating material is (a) it is hygroscopic (6) it has high capacitance (c) it is an organic material (d) none of the above

Last Answer : (a) it is hygroscopic

Description : The insulating material should have (a) low permittivity (b) high resistivity (c) high dielectric strength (d) all of the above

Last Answer : (d) all of the above

Description : The breakdown of insulation of the cable can be avoided economically by the use of (a) inter-sheaths (b) insulating materials with different dielectric constants (c) both (a) and (b) (d) none of the above

Last Answer : (c) both (a) and (b)

Description : The insulating material for cables should (a) be acid proof (b) be non-inflammable (c) be non-hygroscopic (d) have all above properties

Last Answer : (d) have all above properties

Description : The insulating material for a cable should have (a) low cost (b) high dielectric strength (c) high mechanical strength (d) all of the above

Last Answer : (d) all of the above

Description : State what happens to the insulating characteristics of asbestos when it gets wet.

Last Answer : It will become a conductor.

Description : State two fundamental properties of insulating materials.

Last Answer : Insulation resistance and dielectric strength.

Description : What are three types of nonmetallic insulating materials that can be used in a high-temperature environments?

Last Answer : FEP, extruded polytetrafluoroethylene, and silicone rubber.

Description : The process of addition of impurity in pure semiconductor is : a) Doping b) Radiating c) Mixing d) Insulating

Last Answer : d) Insulating

Description : Give four examples of natural insulating materials.

Last Answer : Ans: Examples of the natural insulating materials are cotton, rubber, wood, mica.

Description : Mica is a (A) Dielectric material. (B) Insulating material. (C) Magnetic material. (D) Both insulating and dielectric material.

Last Answer : (D) Both insulating and dielectric material.