A proton and an electron, both at rest initially, combine to form a hydrogen atom in the ground state. A single photon is emit- ted in this process. What is its wavelength？（)

第1题

The scientists are a new element.

A、date from

B、representing

C、in search of

D、twilight

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第2题

Under arena mode, in you fail, you won't gain any awards. Is it true or false?

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第3题

Negative impacts of wood-decay include ( )

A、Weight loss of wood

B、Strength loss of wood

C、Reduced standing timber volume

D、Increased permeability of wood

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第4题

The brain electrical waves is the result of

A、summation of the postsynaptic potentials in one neuron.

B、action potential of one neuron.

C、summation of the postsynaptic potentials of the apical dendrities of neurons.

D、summations of the action potentials on the cell body of the neurons.

E、summation of the action potential on the axon of the neurons.

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第5题

8. The Last Supper --by Leonardo da Vinci Leonardo da Vinci was a true genius who graced this world with his presence from April 15, 1452 to May 2, 1519. He is among the most influential artists in history, having left a significant legacy not only in the realm of art but in science as well, each discipline informing his mastery of the other. Da Vinci lived in a golden age of creativity among such contemporaries as Raphael and Michaelangelo, and contributed his unique genius to virtually everything he touched. Like Athens in the age of Pericles, Renaissance Italy is a summit in human history. Today, no name better seems to symbolize Renaissance age than Leonardo da Vinci. In 1495, Leonardo da Vinci began what would become one of history's most influential works of art - The Last Supper. The Last Supper is Leonardo's visual interpretation of an event chronicled in all four of the Gospels (books in the Christian New Testament). The evening before Christ was betrayed by one of his disciples, he gathered them together to eat, tell them he knew what was coming and wash their feet (a gesture symbolizing that all were equal under the eyes of the Lord). As they ate and drank together, Christ gave the disciples explicit instructions on how to eat and drink in the future, in remembrance of him. It was the first celebration of the Eucharist, a ritual still performed. Specifically, The Last Supper depicts the next few seconds in this story after Christ dropped the bomb shell that one disciple would betray him before sunrise, and all twelve have reacted to the news with different degrees of horror, anger and shock. In The Last Supper, the way in which he isolated Christ at the epicenter of the scene and made each apostle a separate entity, yet at the same time united them all in the moment, is a stroke of genius that subsequent artists throughout history would strive to replicate. Nowadays, Leonardo’s is located in its original place, on the wall of the dining room of the former Dominican convent of Santa Maria delle Grazie, exactly in the refectory of the convent and is one of the most celebrated and well known artworks in the world. Leonardo da Vinci's "Last Supper", a huge painting of 4.60 meters high and 8.80 meters wide was made with tempera and oil on a gypsum preparation instead of the technique commonly used in the fresco period. Several measures have now been implemented to protect the paint from deterioration. To ensure that the fresco is maintained at room temperature, since the last restoration, visitor's' entry has been restricted to a group of 25 people every 15 minutes. Just like William Shakespeare on literature, and Sigmund Freud on psychology, Leonardo's impact on art is tremendous. Throughout his life, Leonardo da Vinci avoided the intrigues of worldly ambitions and vanity. He was a reserved and withdrawn man, not concerned with glory, and yet absolutely sure of the value of his abilities. Along with a small band of contemporary Renaissance figures, Leonardo da Vinci become the center of a movement of artists that has permanently enriched western culture. 16. The underlined word “deterioration” (in Paragraph 7) probably means ________.

A、Betterment.

B、Worsening.

C、Extinction.

D、Distinction.

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第6题

Read the following conversation. What fallacy does Dylan’s argument have? Roman: Unless we build a power plant in this area within the next ten years, we won’t be able to meet the significantly growing demand for electrical power. Dylan: What you’re saying is that you couldn’t care less what happens to the plant life and wildlife in this area or even to human lives that might be dislocated by the building of this dam.

A、Circular reasoning.

B、Red herring.

C、Straw man.

D、Appeal to ignorance.

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第7题

A beam of electrons bombards a sample of hydrogen. Through what potential difference must the electrons have been accelerated if the first line of the Balmer series is to be emitted? ( )

A、35.7 V

B、12.1 V

C、0.6 V

D、569.3 V

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第8题

If the electron in hydrogen atom jumps from the third orbit to second orbit, the wavelength of th emitted radiation is given by ( )

A、5/R

B、36/5R

C、5R/36

D、R/6

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第9题

The longest wavelength in the Lyman series is 121.5 nm and the shortest wavelength in the Balmer series is 364.6 nm. Find the longest wavelength of light that could ionize hydrogen. ( )

A、74.5 mm

B、8.3 nm

C、91.13 nm

D、49.4 fm

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A proton and an electron, both at rest initially, combine to form a hydrogen atom in the ground state. A single photon is emit- ted in this process. What is its wavelength？ （)

A proton and an electron, both at rest initially, combine to form a hydrogen atom in the ground state. A single photon is emit- ted in this process. What is its wavelength？（)