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Q645822 Engenharia Eletrônica

Observe o circuito a seguir.

Imagem associada para resolução da questão

Qual é o valor de VCE relativa ao ponto de operação do circuito acima?

Alternativas
Q645821 Engenharia de Telecomunicações
Considere X e Y como sendo duas variáveis aleatórias. Sabe-se que X é a informação transmitida e Y a informação recebida após o canal; C é a capacidade do canal; I(X;Y) é a Informação Mútua entre as Variáveis X e Y; |x| e |y | são o tamanhos dos alfabetos pertencentes às Variáveis X e Y, respectivamente; e p(x) e p(y) são as probabilidade de ocorrência dos elementos x e y pertencentes às Variáveis X e Y, respectivamente. Dentre as sentenças a seguir, assinale a única opção INCORRETA.
Alternativas
Q645820 Engenharia de Telecomunicações
Considerando as impedâncias da carga e do gerador reais e iguais a R, qual deverá ser a impedância característica de uma linha de transmissão, que interliga o gerador à carga, de modo que a potência fornecida à carga seja máxima?
Alternativas
Q645819 Engenharia de Telecomunicações
Qual a capacidade de um canal binário sem perdas para uma ocorrência de símbolos binários equiprováveis na entrada do canal, sabendo-se que p(x='0')=0,5 e p (x='1')=0,5?
Alternativas
Q645818 Engenharia de Telecomunicações
Considere um receptor super-heterodino de frequência intermediária FI=fo e frequência de sintonia da etapa de RF igual a FRF = 4fo. Dentre as opções abaixo, qual corresponde à frequência do oscilador local?
Alternativas
Q645817 Engenharia de Telecomunicações

Analise as afirmativas abaixo.

I - Existem dois tipos de tecnologia de transmissão em redes: as redes de difusão e as redes ponto a ponto.

II - Ethernet é uma rede de transmissão em anel que permite uma operação de controle descentralizado a velocidades de 10 a 100 Mbps

III- As redes locais tem como características principais as altas taxas de transmissão e baixíssimas taxas de erros.

Assinale a opção correta

Alternativas
Q645816 Engenharia Elétrica

Observe o circuito abaixo.

Imagem associada para resolução da questão

Considerando que o capacitor acima está inicialmente carregado, qual será o valor de vc (t) para t>0.

Alternativas
Q645815 Telecomunicações
Uma portadora cossenoidal de 100 MHz é modulada em frequência, com desvio máximo de 75 KHz, por um sinal cossenoidal de 15 KHz. Qual a largura de faixa, em KHz, ocupada pelo sinal modulado?
Alternativas
Q645814 Engenharia de Telecomunicações
A aplicação dos critérios de Hansen-Woodyard otimiza uma das características de arranjos de antenas na direção longitudinal de propagação (end-fire). À qual característica dos arranjos end-fire o texto se refere?
Alternativas
Q645813 Engenharia de Telecomunicações
Considere um canal telefônico com largura de banda igual a 3,3 kHz e Relação Sinal Ruído de 33 dB. Dentre as opções abaixo, qual a que mais se aproxima da capacidade do canal expressa em bits/s?
Alternativas
Q645812 Engenharia de Telecomunicações
Os sistemas satélites que trabalham nas faixas de frequências compreendidas entre 3,7 a 4,2GHz e 5,925 a 6,425GHz são conhecidos como Banda:
Alternativas
Q645811 Engenharia de Telecomunicações
Em um determinado sistema de comunicações foi calculado que a TOE (Taxa de Onda Estacionária) do guia de ondas que interliga o transmissor à antena é igual a 3. Considerando que a potência de transmissão é de 500 mW, calcule a perda devido a reflexão e, a seguir, assinale a opção correta.
Alternativas
Q645810 Engenharia Elétrica
Um transformador abaixador de 10:1 e 5KVA possui especificada para corrente de secundário a carga máxima de 50 A. Um teste de perda de cobre por meio de curto-circuito dá uma leitura no wattímetro de 100 W . Se a resistência do enrolamento primário for de 0,6Ω , qual é a perda no cobre do secundário?
Alternativas
Q645809 Engenharia de Telecomunicações
Para uma antena cuja área efetiva (abertura) vale Aem = 20m2, quanto vale a sua diretividade máxima para a frequência de operação de 300 MHz?
Alternativas
Q645708 Inglês
Mark the only correct statement according to the text above.
Alternativas
Q645707 Inglês
Mark the only correct statement according to the text above.
Alternativas
Q645706 Inglês
Mark the only correct statement according to the text above.
Alternativas
Q645705 Inglês

The Pilot's Advice

- Daytime. South America. Overcast. Good Visibility.

      On approaching the buoyed deep water channel which led to the breakwater at the entrance to the port, I was in radio contact with the pilot launch, who reported that he was taking a pilot to a vessel anchored further out before bringing us our pilot. On receipt of this information I slowed to a speed to give bare steerage way. Eventually, however, we arrived at the buoyed channel before the pilot launch had returned to us, therefore, I altered course to proceed up the buoyed channel with still minimum power to counteract the cross-tide effect. Once the pilot boarded he ordered "Full Ahead" and moved into the centre of the channel. By this time the other vessel entering the port was close astern of us and rapidly overtaking our vessel. There then developed an intense discussion in the local language between my pilot and the pilot of the overtaking vessel as to who should pass through the breakwater first. Following this discussion my pilot advised me that as we were proceeding further up the harbor we should enter first and so we should maintain full speed. By this time the other vessel's bow was level with our stern and still overhauling us rapidly.

      The situation was allowed by both pilots to develop until the bows were level. I was conning my vessel from the bridge front auxiliary tiller and could feel the intense interaction between the two vessels, I insisted to my pilot that we should reduce speed and allow the other vessel to proceed ahead of us. At this time the pilot of the other vessel stated clearly that my vessel should enter the breakwater first and that he had put his vessel on slow speed, we were then no more than 3 cables from the breakwater. The other vessel dropped rapidly astern and a dangerous situation was averted.

      I think this was a case of the "Senior" pilot on the other vessel bullying the pilot on our vessel and so causing a hazardous and highly unnecessary situation.

                                                  (from the site: www.nautinst.org - MARS Report 93009)

Mark the correct alternative which completes the sentence.

When the tide in an area is moving up, it's said to be _________________.

Alternativas
Q645704 Inglês

The Pilot's Advice

- Daytime. South America. Overcast. Good Visibility.

      On approaching the buoyed deep water channel which led to the breakwater at the entrance to the port, I was in radio contact with the pilot launch, who reported that he was taking a pilot to a vessel anchored further out before bringing us our pilot. On receipt of this information I slowed to a speed to give bare steerage way. Eventually, however, we arrived at the buoyed channel before the pilot launch had returned to us, therefore, I altered course to proceed up the buoyed channel with still minimum power to counteract the cross-tide effect. Once the pilot boarded he ordered "Full Ahead" and moved into the centre of the channel. By this time the other vessel entering the port was close astern of us and rapidly overtaking our vessel. There then developed an intense discussion in the local language between my pilot and the pilot of the overtaking vessel as to who should pass through the breakwater first. Following this discussion my pilot advised me that as we were proceeding further up the harbor we should enter first and so we should maintain full speed. By this time the other vessel's bow was level with our stern and still overhauling us rapidly.

      The situation was allowed by both pilots to develop until the bows were level. I was conning my vessel from the bridge front auxiliary tiller and could feel the intense interaction between the two vessels, I insisted to my pilot that we should reduce speed and allow the other vessel to proceed ahead of us. At this time the pilot of the other vessel stated clearly that my vessel should enter the breakwater first and that he had put his vessel on slow speed, we were then no more than 3 cables from the breakwater. The other vessel dropped rapidly astern and a dangerous situation was averted.

      I think this was a case of the "Senior" pilot on the other vessel bullying the pilot on our vessel and so causing a hazardous and highly unnecessary situation.

                                                  (from the site: www.nautinst.org - MARS Report 93009)

Mark the correct statement according to the following situation.

Ships passing by Rosario Strait, U.S.A., have noticed a new sand bank 6 miles from the entrance to the strait and have informed the port authorities about it. The authorities decide to broadcast this to other vessels in the area as there is a lot of traffic. They say:

Alternativas
Q645703 Inglês

The Pilot's Advice

- Daytime. South America. Overcast. Good Visibility.

      On approaching the buoyed deep water channel which led to the breakwater at the entrance to the port, I was in radio contact with the pilot launch, who reported that he was taking a pilot to a vessel anchored further out before bringing us our pilot. On receipt of this information I slowed to a speed to give bare steerage way. Eventually, however, we arrived at the buoyed channel before the pilot launch had returned to us, therefore, I altered course to proceed up the buoyed channel with still minimum power to counteract the cross-tide effect. Once the pilot boarded he ordered "Full Ahead" and moved into the centre of the channel. By this time the other vessel entering the port was close astern of us and rapidly overtaking our vessel. There then developed an intense discussion in the local language between my pilot and the pilot of the overtaking vessel as to who should pass through the breakwater first. Following this discussion my pilot advised me that as we were proceeding further up the harbor we should enter first and so we should maintain full speed. By this time the other vessel's bow was level with our stern and still overhauling us rapidly.

      The situation was allowed by both pilots to develop until the bows were level. I was conning my vessel from the bridge front auxiliary tiller and could feel the intense interaction between the two vessels, I insisted to my pilot that we should reduce speed and allow the other vessel to proceed ahead of us. At this time the pilot of the other vessel stated clearly that my vessel should enter the breakwater first and that he had put his vessel on slow speed, we were then no more than 3 cables from the breakwater. The other vessel dropped rapidly astern and a dangerous situation was averted.

      I think this was a case of the "Senior" pilot on the other vessel bullying the pilot on our vessel and so causing a hazardous and highly unnecessary situation.

                                                  (from the site: www.nautinst.org - MARS Report 93009)

The correct alternative to complete the sentence below is:

When the men aboard the tug receive the towing line from the ship, they _____________

Alternativas
Respostas
3701: D
3702: D
3703: C
3704: C
3705: D
3706: E
3707: A
3708: C
3709: D
3710: B
3711: D
3712: B
3713: D
3714: D
3715: D
3716: C
3717: B
3718: E
3719: B
3720: A