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Q1. | Electrical contact materials used in switches, brushes and relays must possess |

A. | high thermal conductivity and high melting point [Correct Answer] |

B. | low thermal conductivity and low melting point [Wrong Answer] |

C. | high thermal conductivity and low melting point [Wrong Answer] |

D. | low thermal conductivity and high melting point [Wrong Answer] |

View Answer
Explanation:-
Answer : ADiscuss it below :!! OOPS Login [Click here] is required to post your answer/resultHelp other students, write article, leave your comments |

**Also Read Similar Questions Below :**

⇒ ∈

_{r}is determined by the atomic structure of the dielectric.

TRUE

FALSE

⇒ In a second order system with a unit step input, the speed of response is high if system is

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undamped system

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⇒ The effective length of an 1/2 antenna (Given R

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_{e})

_{max}= 0.34λ

^{2}and η = 120p) is __________ .

0.6348 λ

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0.1587 λ

0.3714 λ

⇒ A horizontal output stage is cutoff for retrace and 40% of trace. If time for each horizontal line is 64 μs and retrace time is 12 μs, the transistor is conducting for about

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31 μs

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⇒ A three state switch has three outputs. These are

low, low and high

low, high, high

low. floating, low

low, high, floating

⇒ Consider the following in C

- An arithmetic operation between integer and an integer gives integer as the result.
- An arithmetic operation between a real and a real constant gives real constant as the result.
- An arithmetic operation between an integer constant and a real constant is not valid.

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1 and 2 only

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1 and 3 only

⇒ The function shown in figure, can represent a probability density function for A ________

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**Assertion (A):** In an intrinsic semiconductor J = (μ_{n} x μ_{p})*en*_{i}.

**Reason (R):** Intrinsic charge concentration *n*_{i} at temperature T is given by *n*_{i}^{2} = A_{0} T^{3} *e*^{-EG0/kT}.

Both A and R are true and R is correct explanation of A

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A is true but R is false

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⇒ An e-mail message can be sent to many recipients.

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(X + Y) (X + Y)

(X + Y) (X + Y)

(X + Y) (X + Y)

(X + Y) (X + Y)

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Match the following:

List I | List II | ||
---|---|---|---|

A. | C | 1. | 7 eV |

B. | Si | 2. | 1.15 eV |

C. | Ge | 3. | 0.75 eV |

D. | Sn | 4. | 0.1 eV |

E. | Pb | 5. | 0 eV |

A-2, B-3, C-4, D-5, E-1

A-1, B-2, C-3, D-4, E-5

A-3, B-1, C-2, D-5, E-4

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⇒ If

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**Reason (R):** Diffusion of carriers occurs in semiconductors.

Both A and R are true and R is correct explanation of A

Both A and R are true but R is not a correct explanation of A

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⇒ For the truth table of the given figure

A + B + C

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B

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T

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