# GATE (Graduate Aptitude Test in Engineering) Physics: Questions 274 - 278 of 659

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### Passage

A plane electromagnetic wave has the magnetic field given by,

where, is the wave number and are the Cartesian unit vector in directions, respectively.

## Question 274 (2 of 2 Based on Passage)

Appeared in Year: *2011*

### Question

MCQ▾The electric field corresponding to the above wave is given by –

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | ||

d. |

## Question 275

Appeared in Year: *2010*

### Question

MCQ▾The value of the integral , where the contour is the unit circle | |= 1 is –

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | 0 | |

d. |

## Question 276

Appeared in Year: *2010*

### Question

MCQ▾The Bloch theorem states that within a crystal, the wavefunction, of an electron has the from –

### Choices

Choice (4) | Response | |
---|---|---|

a. | where is an arbitrary function and is a reciprocal lattice vector | |

b. | where , is a lattice and is a reciprocal lattice vector | |

c. | where , is a lattice vector and is an arbitrary vector | |

d. | , where is an arbitrary function and is an arbitrary vector |

## Question 277

Appeared in Year: *2010*

### Question

MCQ▾Consider an anti – symmetric tensor with the indices and running from to . The number of independent components of the tensor is –

### Choices

Choice (4) | Response | |
---|---|---|

a. | 9 | |

b. | 3 | |

c. | 6 | |

d. | 10 |

## Question 278

Appeared in Year: *2010*

### Question

MCQ▾Two states of an atom have definite parities. An electric dipole transition between these states is

### Choices

Choice (4) | Response | |
---|---|---|

a. | Allowed if both the states have even parity | |

b. | Allowed if both the states have odd parity | |

c. | Not allowed unless a static electric field is applied | |

d. | Allowed if the two states have opposite parities |