相关试题
【单选题】
临时用电器的剩余电流保护动作电流值不大于【】mA。___
【单选题】
户外落地变压器外廓与建筑物外墙距离小于【】m时,应考虑对建筑物的防火要求。___
【单选题】
10kV跌落式熔断器一般安装在柱上配电变压器【】侧。___
A. 高压侧
B. 两侧
C. 低压侧
D. 线路
【单选题】
单相三孔插座安装时,必须把接地孔眼(大孔)装在【】。___
【单选题】
国家实行分类电价和分时电价,分类标准和分时办法由【】确定。___
A. 县人民政府
B. 市人民政府
C. 省人民政府
D. 国务院
【单选题】
避雷器主要用来保护架空线路中的【】和变、配电室运行段的首端以及雷雨季节经常断开而电源侧又带电压的隔离开关或油断路器等。___
A. 过负荷
B. 绝缘薄弱环节
C. 过负荷和短路
D. 低电压
【单选题】
因违约用电或窃电造成供电企业的供电设施损坏的责任者,【】供电设施的修复费用或进行赔偿。___
A. 必须承担
B. 必须办理
C. 不承担
D. 可以交纳
【单选题】
大功率三相电机启动将不会导致【】。___
A. 电压问题
B. 电压正弦波畸变
C. 高次谐波
D. 电网三相电压不平衡
【单选题】
接户线受电端的对地面垂直距离:1~10kV不应小于4m,1kV不应小于【】。___
A. 3.5m
B. 2.5m
C. 1.5m
D. 0.5m
【单选题】
直埋电缆必须在上面覆盖一层不小于100mm厚的软土或沙层,覆盖层上面用混凝土板或砖块覆盖,宽度超过电缆两侧各【】mm,防止电缆受机械损伤。___
【单选题】
高压电容器通常采用【】保护。___
A. 延时
B. 熔断器
C. 热继电器
D. 剩余电流保护
【单选题】
当终端时钟误差超过允许值后,主站启动【】,终端生成对时事件,可由主站召测或终端主动上报对时是否成功。___
A. 主站对时
B. 电能表对时
C. 采集终端对时
D. 卫星对时
【单选题】
《国家电网公司供电服务规范》规定:对客户投诉,应100%跟踪投诉受理全过程,【】天内答复。___
【单选题】
10kV跌落式熔断器安装在户外,要求相间距离大于【】。___
A. 0.2m
B. 0.35m
C. 0.4m
D. 0.5m
【单选题】
重量大于300kg及以上的底盘、拉线盘一般采用【】法吊装。___
A. 吊车
B. 人力推下
C. 人字扒杆
D. 简易方法
【单选题】
《功率因数调整电费办法》可促使用户改善【】、提高供电能力、节约电能的作用。___
A. 合理用电
B. 生产成本
C. 电压质量
D. 经济效益
【单选题】
一电容接到f=50Hz的交流电路中,容抗Xc=240Ω,若改接到f=150Hz的电源电路中,则容抗Xc为【】Ω。___
A. 80
B. KONG
C. 160
D. 720
【单选题】
当电路正常运行时,流过熔断器的电流小于熔体的【】,熔体正常发热温度不会使熔体熔断,熔断器长期可靠运行。___
A. 额定电流
B. 最大电流
C. 最小电流
D. 温度
【单选题】
对脚扣作人体冲击试验,试验时将脚扣系于混凝土杆离地【】m左右。___
A. 0.8
B. 0.5
C. 1
D. 0.9
【单选题】
用四极法测量土壤电阻率电极埋深要小于极间距离的【】。___
A. 1/30
B. 1/20
C. 1/50
D. 1/40
【单选题】
单相三孔插座安装时:必须把接地孔眼(大孔)装在上方,同时规定接地线桩必须与接地线连接,即【】。___
A. 左零右火
B. 左零右火上接地
C. 右零左火上接地
D. 左地右火上零
【单选题】
水平接地体相互间的距离不应小于【】m。___
【单选题】
人体通过的电流值与通电时间的乘积,对人身的安全是一个界限,国际电工委员会规定交流【】mA以下为安全值。___
【单选题】
一个实际电源的端电压随着负载电流的减小将【】。___
A. 降低
B. 升高
C. KONG
D. 稍微降低
【单选题】
LGJ-95导线使用压接管接续时,钳压压口数为【】个。___
【单选题】
能够正常有效且连续为全部用电负荷提供电力的电源是指【】。___
A. 主要电源
B. 主用电源
C. KONG
D. 主供电源
【单选题】
为保证事故处理时熔管、熔丝的互换性,减少事故处理备件数量,一个维护区域内宜固定使用【】型号跌落式熔断器。___
【单选题】
电费呆账是指个别单位因经营不善等多种原因造成企业破产,电费确实【】的账款。___
A. 无法收回
B. 收回有些困难
C. 减账
D. 可以自行消核
【单选题】
用户用电设备容量在【】千瓦及以下或需用变压器容量在50千伏安及以下者,可采用低压三相四线制供电,特殊情况也可采用高压供电。___
【单选题】
水平接地体的选择优先采用圆钢,一般直径为【】。___
A. 2~4mm
B. 5~7mm
C. 8~10mm
D. 12~14mm
【单选题】
我国交流电的标准频率为50Hz,其周期为【】s。___
A. 0.01
B. 0.02
C. KONG
D. 0.2
【单选题】
【】是电力企业向用户收费的凭证,也是专为销售电能产品后直接开给消费者的账单。___
A. 电费发票
B. 电费收据
C. 计算清单
D. 结算凭证
【单选题】
测量绝缘子的绝缘电阻,选择兆欧表的额定电压应为【】V。___
A. 500
B. 1000
C. 1500
D. 2500或5000
【单选题】
双处或三处开关控制单灯。可采用两只双控开关,分装在不同位置,常应用在楼梯或走廊照明,在楼上楼下或走廊两端均可独立控制一盏灯。若需三处控制同一盏灯时,可装两只双控开关和【】以达到目的。___
A. 一只双控开关
B. 一只多控开关
C. 二只单控开关
D. 二只双控开关
【多选题】
低压熔断器具有、体积小、重量轻等优点,因而得到广泛应用。___
A. 结构简单
B. 价格便宜
C. 使用维护方便
D. 容量大
【多选题】
交流接触器的构造主要包括。___
A. 触头系统
B. 电磁系统
C. 灭弧装置
D. 其他部分
【多选题】
在测量电气设备绝缘电阻时,影响绝缘电阻的因素主要有。___
A. 被测设备环境温度相对增大时,绝缘电阻降低
B. 被测设备表面脏污会使其绝缘电阻显著下降
C. 被测设备停电后,放电的残余电荷或试验后放电的残余电荷,造成试验或再次试验的绝缘偏大或偏小
D. 电容耦合,带电设备将使被测的设备带上一定的感应电压,将影响其绝缘电阻测量值
【多选题】
为防止电缆试验过程中发生触电伤害,在变更接线时下列哪些做法是正确的。___
A. 必须断开试验电源
B. 被试电缆逐相多次放电
C. 将升压设备的高压部分短路
D. 将升压设备的高压部分接地
【多选题】
绕组相间和匝间,会导致绕组电流增大,三相电流不平衡,使电动机过热。___
推荐试题
【单选题】
Refer to the exhibit line in this configuration prevents the help Desk user from modifying the interface configuration.___
A. Privilege exec level 10 interface
B. Privilege exec level 9 configure terminal
C. Privilege exec level 7 show start-up
D. Username HelpDesk privilege 6 password help
【单选题】
You have been tasked with blocking user access to websites that violate company policy, but the sites use dynamic IP addresses. What is the best practice for URl filtering to solve the problem?___
A. Enable URL filtering and use URL categorization to block the we bsites that violate company
B. Enable URL filtering and create a blacklist to block the websites that violate company policy
C. Enable URL filtering and create a whitelist to block the websites that violate company policy
D.
E. nable URL filtering and use URL categorization to allow only the websites that company policy allows users to access.
【单选题】
Within an 802. 1x-enabled network with the auth Fail feature configured, when does a switch port get placed into a restricted VLAN?___
A. When a conected client fails to authenticate after a certain number of attempts.
B. if a connected client does not support 802. 1x
C. when AAA new-model is ena bled
D. after a connected client exceeds a specified idle time
E. when 802. 1x is not globally enabled on the Cisco Catalyst switch
【单选题】
Which type of attack does a proxy firewall protect against ?___
A. cross-site scripting attack
B. worm traffic
C. port scanning
D. DDoS attacks
【单选题】
When an administrator initiates a device wipe command from the ISE, what is the immediate effect?___
A. It requests the administrator to choose between erasing all device data or only managed corporate data.
B. It requests the administrator to enter the device pin or password before proceeding with the operation
C. It notifies the device user and proceeds with the erase operation
D. It immediately erases all data on the device
【单选题】
What is a valid implicit permit rule for traffic that is traversing the ASa firewall?___
A. ARPs in both directions are permitted in transparent mode only
B. Unicast IPv4 traffic from a higher security interface to a lower security interface is permittee in routed mode only.
C. Unicast IPv6 traffic from a higher security interface to a lower security interface is permitted in transparent mode only.
D. Only BPDUs from a higher security interface to a lower secur ity interface are permitted in transparent mode.
E. Only BPDUs from a higher security interface to a lower secur ity interface are permitted in routed mode
【单选题】
A specific URL has been identified as containing malware. What action can you take to block users from accidentally visiting the URl and becoming infected with malware ?___
A. Enable URL filtering on the perimeter router and add the URls you want to block to the router's local URL list
B. Enable URL filtering on the perimeter firewall and add the URls you want to allow to the router's local URL list.
C. Enable URL filtering on the perimeter router and add the URls you want to allow to the firewall's local URL list
D. Create a blacklist that contains the URl you want to block and activate the blacklist on the perimeter rout
E. Create a whitelist that contains the URLs you want to allow and activate the whitelist on the perimeter router.
【单选题】
How does PEAP protect the EAP exchange ?___
A. It encrypts the exchange using the server certificate
B. It encrypts the exchange using the client certificate
C. It validates the server-supplied certificate,and then encrypts the exchange using the client certificate
D. It validates the client-supplied certificate,and then encrypts the excha nge using the server certificate
【单选题】
Which feature of the Cisco Email Security Appliance can mitigate the impact of snowshoe spam and sophisticated phishing attacks?___
A. contextual analysis
B. holistic understanding of threats
C. graymail management and filtering
D. signature-based IPS
【单选题】
Refer to the exhibit【nat (inside,outside)dunamic interface】 Which translation technique does this configuration result in?___
A. DynamIc PAT
B. Dynamic NAT
C. Twice NAT
D. Static NAT
【单选题】
Refer to the exhibit which are repre sents the data center?___
【单选题】
While trouble shooting site-to-site VPN, you issued the show crypto isakmp sa command. What does the given output show?___
A. IKE Phase 1 main mode was created on 10.1.1.5, but it failed to negotiate with 10.10 10.2
B. IKE Phase 1 main mode has successfully negotiated between 10.1.1.5 and 10.10..
C. IKE Phase 1 aggressive mode was created on 10.1.1.5, but it failed to negotiate with
【单选题】
Refer to the exhibit All ports on switch 1 have a primary vLan of 300 Which devices can host 1 reach?___
A. host 2
B. server
C. host 4
D. other devices within VLAN303
【单选题】
Which option is the cloud-based security service from Cisco the provides URL filtering, web browsing content security, and roaming user protection?___
A. Cloud Web service
B. Cloud Advanced Malware Protection
C. Cloud We b Security
D. Cloud Web Protection
【单选题】
How can you detect a false negative on an IPS?___
A. View the alert on the ips
B. Review the ips log
C. Review the is console
D. Use a third- party system to perform penetration testing.
E. Use a third- party to audit the next generation firewall rules
【单选题】
If a switch port goes directly into a blocked state only when a superior BPDU is received, what mechanism must be in use?___
A. STP BPDU guard
B. Loop guard
C. EtherChannel guard
D. STP Root guard
【单选题】
what improvement does EAP-FASTv2 provide over EAP-FAST? ___
A. It allows multiple credentials to be passed in a single EAP exchange.
B. It supports more secure encryption protocols
C. It allows faster authentication by using fewer packets.
D. It addresses security vulnerabilities found in the original protocol
【单选题】
When users login to the Client less Ssl Vpn using https://209.165.201.2/test ,which group policy will be applied?___
A. test
B. clientless
C. sales
D. DfitGrp Policy
E. Default RAGroup
F. Default WEB VPN
G. roup
【单选题】
Which user authentication method is used when users login to the Clientless SSLVPN portal using https://209.165.201.2/test?___
A. AAA with LOCAL database
B. AAA with RADIUS server
C. Certificate
D. :Both Certificate and aaa with LoCAL database
E. Both Certificate and AAA with RADIUS server
【单选题】
What' s the technology that you can use to prevent non malicious program to runin the computer that is disconnected from the network?___
A. Firewall
B. Sofware Antivirus
C. Network IPS
D. Host IPS
【单选题】
Which statement about the communication between interfaces on the same security level is true?___
A. Interfaces on the same security level require additional configuration to permit interinterface communication
B. Configuring interfaces on the same security level can cause asymmetric routing
C. All traffic is allowed by default between interfaces on the same security level
D. You can configure only one interface on a n individual security level
【单选题】
Which product can be used to provide application layer protection for tcp port 25 traffic?___
A. ESA
B. CWS
C. WSA
D. ASA
【单选题】
which iPS mode is less secure than other options but allows optimal network through put ?___
A. inline mode
B. inline-bypass mode
C. transparent mode
D. Promiscuous mode
【单选题】
Which feature of the Cisco Email security Appliance can mitigate the impact of snowshoe spam and sophisticated phishing attack?___
A. reputation based filtering
B. signature based IPS
C. contextual analysis
D. graymail management and filtering
【单选题】
Which type of social-engineering attack uses normal tele phone service as the attack vector?___
A. smishing
B. dialing
C. phishing
D. vishing
【单选题】
Which quantifiable item should you consider when you organization adopts new technologies?___
A. exploits
B. vulnerability
C. threat
D. Risk
【单选题】
Referencing the ClA model, in which scenario is a hash- only function most appropriate ?___
A. securing data at rest
B. securing real-time traffic
C. securing data in files
D. securing wireless transmissions
【单选题】
Which ports must be open between a aaa server and a microsoft server to permit Active Directory authentications?___
A. 445 and 389
B. 888 and 3389
C. 636 and 4445
D. 363 and 983
【单选题】
Refer to the exhibit for which reason is the tunnel unable to pass traffic___
A. the tunnel is failing to receive traffic from the remote peer
B. the local peer is unable to encrypt the traffic
C. the ip address of the remote peer is incorrect
D. UDP port 500 is blocked
【单选题】
Which type of attack can exploit design flaws in the implementation of an application without___
A. DHCP starvation attacks
B. low-rate dos attacks
C. application DDos flood attacks
D. application DDoS flood attacks
E. volume-based DDoS attacks
【单选题】
How can you protect CDP from reconnaissance attacks?___
A. Enable dynamic ARP inspection on all untrusted ports.
B. Enable dot1x on all ports that are connected to other switches.
C.
D. isable CDP on ports connected to endpoints.
【单选题】
Which type of attack can exploit design flaws in the implementation of an application without ?___
A. DHCP starvation attacks
B. low-rate dos attacks
C. application DDos flood attacks
D. application DDoS flood attacks
E. volume-based DDoS attacks
【单选题】
Which option is a key security compone nt of and MDM deployment ?___
A. using network-specific installer packages
B. using an application tunnel by default
C. using self-signed certificates to validate the server
D. using MS-CHAPv2 as the primary
E. AP method
【单选题】
Which Firepower Management Center feature detects and block exploits and hack attempts?___
A. Content blocker
B. file control
C. intrusion prevention
D. advanced malware protection
【单选题】
hich description of the nonsecret numbers that are used to start a Diffie- Hellman exchange is ture?___
A. They are preconfigured prime integers.
B. They are large pseudorandom numbers.
C. They are very small numbers chosen from a table of known valuses
D. They are numeric values extracted from ha shed system hostnames
【多选题】
Which two characteristics of an application layer firewall are true?___
A. provides stateful firewal functionality
B. has low processor usage
C. provides protection for multiple applications
D. provides rever se proxy services
E. is immune to URL manipulation
【多选题】
Which two devices are components of the BYOD architectural framework?___
A. Nexus 7010 switch
B. Cisco 3945 Router
C. Identify Services Engine
D. Wireless Access oints
E. Prime Infrastructure
【多选题】
Which two actions can a zone based firewall take when looking at traffic? ___
A. forward
B. inspect
C. drop
D. broadcast
E. filter
【多选题】
n which two situations should you use in-band management?___
A. when management applications need concurrent access to the device
B. when you require administrator access from multiple locations
C. when a network device fails to forward packets
D. when you require ROMMON access
E. when the control plane fails to respond
【多选题】
What are two ways to prevent eavesdropping when you perform device management tasks?___
A. Use an SSH connection.
B. Use SNMPv3
C. Use out-of-band management
D. Use SNMP
E. Use in-band management