【单选题】
在一组TG450型蓄电池中，若有两块蓄电池反极则蓄电池端电压为_______V。___
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【单选题】
客车电气综合控制柜的主电路中接有DC600V_______[6～150mA可调，共分六挡]，当漏电值超过设定值时，自动切断供电，同时漏电指示灯亮。___
A. 在线绝缘检测装置
B. 绝缘检测装置
C. 漏电报警装置
D. 轴温报警装置
【单选题】
玻璃的耐热等级为_______。___
【单选题】
轴报器出库前须工作正常，轴与轴同侧温差不大于_______度。___
【单选题】
25T型客车在正常供电时，空调、客室电热等负载由_______35kV•A逆变器供电。___
【单选题】
25T型客车的逆变器箱主电路为_______电路，采用IGBT作为开关器件，具有开关频率高、驱动简单、损耗低的特点。___
A. 单相桥式大电流型
B. 单相桥式电压型
C. 三相桥式电压型
D. 三相桥式大电流型
【单选题】
25T型客车的逆变器，在输出额定电压、额定电流和规定的负载功率因数状态时，逆变器的效率应大于_______。___
A. 80％
B. 90%
C. 75％
D. 85％
【单选题】
25T型客车的逆变器应有一定的承受输入_______的能力。___
A. 电流突变
B. 电压突变
C. 功率突变
D. 功率因数突变
【单选题】
25K型空调客车的空调控制柜[KLC40C-1T1]中KT1，KT2的时间设定值为_______。[1.0分]___
A. 30s和35s
B. 60s和70s
C. 20s和40s
D. 3min和5min
【单选题】
25K型空调客车的空调控制柜[KLC40C-1T1]的客室电加热控制回路须经过_______中3Q，4Q的控制。___
A. 温度控制柜
B. 电源控制柜
C. 电茶炉控制箱
D. 照明控制柜
【单选题】
25T型客车的逆变器输出三相负载允许_______不平衡。___
A. 30％
B. 20%
C. 10％
D. 15％
【单选题】
25T型客车的逆变器在20kW负载状态下稳定运行时，突加制冷压缩机负载[功率为4.5～5.5kW]，逆变器_______。___
A. 必须重新启动
B. 必须停机，3～5min再启动
C. 应能正常运行
D. 将会跳闸
【单选题】
25T型客车的充电器进行模拟过分相试验：充电器每工作_______，输入电源断电10s，充电器应能正常工作，该项试验连续模拟10次。___
A. 10min
B. 1min
C. 5min
D. 20min
【单选题】
25T型客车的充电器在额定输入状态下，突加、突减_______额定负载，充电器应能正常工作。___
A. 30％
B. 50%
C. 45％
D. 25％
【单选题】
MS730CP6C塞拉门是高速旅客列车使用的系列化外摆塞拉门，控制方式为_______。___
A. 气压控制
B. 电信号控制
C. 计算机控制
D. 液压控制
【单选题】
MS730CP6C塞拉门的车门系统具有_______功能。___
A. 防断电
B. 防挤压
C. 防过压
D. 防漏电
【单选题】
对全车性能试验的车辆应在车体两侧涂打_______的白色标记。___
A. 一条宽为50mm
B. 一条宽为100mm
C. 两条宽为50mm
D. 两条宽为100mm
【单选题】
爆炸危险品专用车的车体中部四周涂打宽为200mm的_______色带，并在色带中部涂打“危险”字样。___
【单选题】
车辆滚动轴承使用的润滑脂是_______。___
A. 3号钙基脂
B. 3号钠基脂
C. 3号锂基脂
D. 3号钙钠基脂
【单选题】
_______手柄处是不绝缘的。___
A. 斜口钳
B. 剥线钳
C. 电工刀
D. 断线钳
【单选题】
车轴与车轮的配合属于_______。___
A. 间隙配合
B. 过盈配合
C. 过渡配合
D. 动配合
【单选题】
车辆检修限度中，属于最大限度的是_______。___
A. 厂修限度
B. 段修限度
C. 辅修限度
D. 运用限度
【单选题】
25T型客车的蓄电池组应有短路保护，各极对箱体间的绝缘电阻应不小于_______。___
A. 20M
B. 10M
C. 15M
D. 50M
【单选题】
检修限度分为中间限度和_______限度。___
【单选题】
对于电路的任一闭合回路，从回路任一点出发，沿回路绕行1周，电位上升之和_______电位下降之和。___
【单选题】
在直流电路中，当负载获得最大功率时，电源的效率为_______。___
A. 30％
B. 50％
C. 80％
D. 100％
【单选题】
在电阻的色环标值识别法中，其中第_______表示阻值的误差。___
A. 一色环
B. 二色环
C. 三色环
D. 四色环
【单选题】
电容器按所用电介质的不同，分为纸介电容器、云母电容器、_______、电解电容器等。___
A. 固定电容器
B. 可变电容器
C. 瓷介电容器
D. 半可变微调电容器
【单选题】
在纯电阻交流电路中，电压与电流的相位关系是_______。___
A. 同相
B. 反相
C. 电压导前电流90°
D. 电压滞后电流90°
【单选题】
硅、锗、硒等物体属于_______。___
A. 导体
B. 半导体
C. 超导体
D. 绝缘体
【单选题】
交流接触器短路环的作用是_______。___
A. 励磁
B. 增加电磁吸力
C. 节电运行
D. 消除振动和噪声
【单选题】
求三相对称负载的有功功率，_______是正确的。___
A. P＝Ｕ相I相cos
B. P＝U相Ｉ相sin
C. P＝Ｕ线Ｉ线sin
D. P＝Ｕ线Ｉ线cos
【单选题】
交流接触器的线圈电压在额定电压的_______时，可以可靠地工作。___
A. 60％～80％
B. 70％～120％
C. 请输入内85％～105％
D. 100％～115％
【单选题】
接触器触头采用桥式双断口结构，其目的是利用_______原理灭弧。___
A. 电动力灭弧
B. 磁吹灭弧
C. 窄缝灭弧
D. 栅片灭弧
【单选题】
调整和检查自动空气开关和主接触器的触头应注意触头的_______。___
A. 开距、压力
B. 压力、超程
C. 压力、开距、超程
D. 开距、超程
【单选题】
_______不会造成接触器铁芯振动和噪声。___
A. 短路环损坏或脱落
B. 铁芯端面有锈蚀
C. 线圈电压过低
D. 反作用弹簧力不足
【单选题】
电动机是把_______的设备。___
A. 机械能转换成电能
B. 电能转换成机械能
C. 化学能转换成电能
D. 化学能转换成机械能
【单选题】
异步电动机定子主要由_______组成。___
A. 铁芯、绕组
B. 铁芯、机座
C. 铁芯、绕组、机座
D. 铁芯、绕组、转轴
【单选题】
三角形连接的三相鼠笼式异步电动机，若误接成星形，则输出功率_______。___
A. 下降
B. 不变
C. 增大
D. 视具体情况而定
【单选题】
_______不是直流电动机调速的方法。___
A. 改变电枢回路电阻值
B. 改变励磁电流
C. 改变电枢电压
D. 改变转差率
【单选题】
电刷火花的等级有_______。___
推荐试题
【多选题】
When using the Adaptive Security Device Manager（ASDM), which two options are available to add a new root certificate？___
A. Install from SFTP server
B. Usehttps
C. Install from a file
D. Use LDAP
E. Use SCEP
【多选题】
Which two SNMPv3 services support its capabilities as a secure networ k manage protocol？ ___
A. access control
B. the shared secret key
C. authentication
D. authorization
E. accounting
【多选题】
Which two statements about routed firewall mode are true ？___
A. The firewall acts as a routed hop in the network
B. This mode conceals the presence of the firewall
C. The firewall requires a unique iP address for each interface
D. This mode allows the firewall to be added to an existing networ k with minimal additional configuration By default， this mode permits most traffic to pass throug
【多选题】
Which two statements describe DHCP spoofing attacks？___
A. They are used to perform man-in- the-middle attacks
B. They can access most network devices
C. They can modify the flow of traffic in transit. LNGKAIG
D. They protect the identity of ti attacker by masking the DHCP address
E. They can physically modify the network gateway
【多选题】
Which two types of VLANs using PVLANs are valid？___
A. isolated
B. promiscuous
C. backup
D. secondary
E. community
【多选题】
What are two limitations of the self-zone policies on a zone-based firewall？___
A. They are unable to block Https traffic
B. They restrict SNMP traffic.
C. They are unable to support Https traffic
D. They are unable to implement application inspection
E. They are unable to perform rate limiting
【多选题】
Which two descriptions of TACACS+ are true？ ___
A. The TACACS+ header is unencrypted
B. It combines a uthentication and authorization
C. It uses TCP as its transport protocol
D. Only the password is encrypted.
E. It uses UDP as its transport protocol.
【多选题】
Which two actions does an IPS perform？ ___
A. it spans the traffic
B. it reflects the traffic back to the sender
C. it encrypts the traffic
D. it terminates the user session or connection of the attacker
E. it reconfigures a device to block the traffic
【多选题】
In which form of fraud does an attacker try to learn information such as login credenti account information by ma squerading as a reputable entity or person in email， IM or communication channels ?___
A. phishing
B. Smurfit
C. Hacking
D. Identity Spoofing
【多选题】
Which two ESA services are available for incoming and outgoing mails ？___
A. anti-DoS
B. reputation filter
C. antispam
D. content filter
E. DLP
【多选题】
What are two reasons to recommend SNMPv 3 over SNMPv2？___
A. SNMPv3 is secure because you can configure authe ntication and privacy
B. SNMPv3 is insecure because it send in formation in clear text
C. SNMPv2 is insecure because it send information in clear text
D. SNMPv3 is a Cisco proprietary protocol
E. SNMPv2 is secure because you can configure authentication and privacy
【多选题】
Which two actions can a zone- based firewall apply to a packet as it transits a zone pair？___
A. drop
B. inspect
C. queue
D. quarantine
【单选题】
Which security principle has been violated if data is altered in an unauthorized manner？___
A. accountability
B. confidentiality
C. availability
D. integrity
【单选题】
Which IKE Phase 1 parameter can you use to require the site-to-site VPN to use a pre-shared ？___
A. encryption
B. authentication
C. group
【单选题】
Which command successfully creates an administrative user with a password of "cisco"on a Cisco router?___
A. username Operator privilege 7 password cisco
B. username Operator privilege 1 password cisco
C. username Operator privilege 15 password cisco
D. username Operator password cisco privilege 15
【单选题】
Which EAP method authenticates a client against Active Directory without the use of client-side 802.1X certificates？___
A. EAP-TLS
B. EAP-MSCHAPv2
C. EAP-PEAP
D.
E. AP-GTC
【单选题】
What is a limitation of network-based IPS？___
A. It must be in dividually configured to support every operating system on the network.
B. It is most effective at the in dividual host level
C. It is unable to monitor attacks across the entire netw ork
D. Large installations require numerous sensors to fully protect the network
【单选题】
When would you configure the ip dhcp snooping trust command on a sw itch？___
A. when the switch is connected to a DHCP server
B. when the switch is working in an edge capacit
C. when the switch is connected to a client system
D. when the switch is serving as an aggregator
【单选题】
How does the 802. 1x supplicant communicate with the authentication server？___
A. The supplicant creates EAP packets and sends them to the authenticator, which encapsulates them into RADIUS and forwards them to the authentication server.
B. The supplicant creates RADIUS packets and sends them to the authe nticator, which encapsulates the m into EAP and forwards them to the a uthentication server.
C. The supplicant creates RADIUS packets and sends them to the authenticator, which translates them into eap and forwards them to the a ut hentication server
D. The supplicant creates
E. AP packets and sends them to the authe nticator, which translates them into radius and forwards them to the authentication server.
【单选题】
Which command do you enter to verify the phase I status of a VPN connection？___
A. sh crypto se ssion
B. debug crypto isakmp
C. sh crypto isakmp sa
D. sh crypto ipsec sa
【单选题】
Refer to the exhibit. what is the e ffect of the given configuration？___
A. It enables authentication，
B. It prevents keychain authentication.
C. The two routers receive normal updates from one another.
D. The two device s are able to pass the message digest to one another.
【单选题】
Which command can you enter to configure OSPF to use hashing to authenticate routing updates？___
A. ip ospf aut hentication message-digest
B. neighbor 192 168.0 112 cost md5
C. ip ospf priority 1
D. ip ospf aut hentication-key
【单选题】
Which command can you enter to verify the status of Cisco lOS Resilient Configuration on a Cisco router?___
A. show secure bootset
B. secure boot-image
C. show binary file
D. ure boot-config
【单选题】
A user on your network inadvertently activates a botnet program that was received as an emai attachment. Which type of mechanism does Cisco Firepower use to detect and block only the botnet attack？___
A. network-based access control rule
B. reputation-based
C. user-ba sed access control rule
D. botnet traffic filter
【单选题】
What does the policy map do in CoPP？___
A. defines service parameters
B. defines packet selection parameters
C. defines the packet filter
D. define s the action to be performed
【单选题】
How is management traffic isolated on a Cisco ASR 1002？___
A. Traffic isolation is done on the vlan level
B. There is no management traffic isolation on a Cisco ASR 1002
C. Traffic is isolated based upon how you configure routing on the device
D. The management interface is configured in a special vRF that provides traffic isolation from the default routing table
【单选题】
Which statement about NaT table evaluation in the asa is true？___
A. After-auto NAT polices are appl d first
B. Manual NAT policies are applied first
C. the asa uses the most specific match
D. Auto NAT policies are applied first
【单选题】
Which information can you display by executing the show crypto ipsec sa command？___
A. ISAKMP SAs that are established between two peers
B. recent changes to the IP address of a peer router
C. proxy infor mation for the connection between two peers
D. IPsec SAs established between two peers
【单选题】
How can you prevent NAT rules from sending traffic to incorrect interfaces？___
A. Assign the output interface in the NAT statement
B. Add the no-proxy-arp command to the nat line.
C. Configure twice NAT instead o bject NAT. 5
D. Use packet-tracer rules to reroute misrouted NAT entries.
【单选题】
What term can be defined as the securing， control， and identification of digital data？___
A. cryptography
B. crypto key
C. cryptoanalysis
D. cryptology
【单选题】
Which feature in the dNS security module provide on and off network DNS protection？___
A. Data Loss Prevention
B. Umbrella
C. Real-time sandboxing
D. Layer-4 monitoring
【单选题】
Which a dverse consequence can occur on a network without BPDu guard ?___
A. The olde st switch can be elected as the root bridge
B. Unauthorized switches that are connected to the network can cause spanning-tree loops
C.
D. ouble tagging can cause the switches to experience CAM table overload.
【单选题】
What configuration is required for multitenancy ?___
A. shared infrastructure
B. multiple carriers
C. co-located resources
D. multiple separate zones
【单选题】
Why does ISE require its own certificate issued by a trusted CA？___
A. ISEs certificate allows guest devices to validate it as a trusted network device
B. It generates certificates for guest devices ba sed on its own certificate
C. It requests certificates for guest devices from the Ca server based on its own certificate.
D. ISE's certificate allows it to join the network security framework
【单选题】
which attack involves large numbers of ICMP packets with a spoofed source IP address？___
A. smurf attack
B. Teardrop attack
C. Nuke attack
D. SYN Flood attack
【单选题】
Which statement about interface and global access rules is true？___
A. Interface access rules are processed before global access rules.
B. Global access rules apply only to outbound traffic， but interface access rules can be applied in either direction
C. The implicit allow is proce ssed after both the global and interface access rules
D. If an interface access rule is applied， the global access rule is ignored
【单选题】
Which type of malicious software can create a back-door into a device or network？___
A. bot
B. worm
C. virus
D. Trojan
【单选题】
Which security term refers to the like lihood that a weakness will be exploited to cause damage to an asset？___
A. threat
B. risk
C. countermeasure
D. vulnerability
【单选题】
Which IPS detection method examines network traffic for preconfigured patterns？___
A. signature-based detection
B. honey-pot detection
C. anomaly-based detection
D. policy-based detection
【单选题】
What is an advantage of split tunneling ？___
A. It allows users with a VpN connection to a corporate network to access the internet with sending traffic across the cor porate network.
B. It allows users with a vpn connection to a corporate network to access the internet by using the vPN for security.
C. It protects traffic on the private network from users on the public network
D. It enables the VPN server to filter traffic more efficiently
