【单选题】
在RL串联的单相交流电路中,有功功率的计算公式为___。
A. P=UIcosψ
B. P=UIsinψ
C. P=UI
D. P=I2Z
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相关试题
【单选题】
基尔霍夫第一定律又叫节点电流定律,说的是___。
A. 流入某节点电流的和为零
B. 流出某节点电流的和为零
C. 流入节点的电流之和等于流出节点的电流之和
D. 一个回路中各处电流相等
【单选题】
一个2μF与一个4μF的电容器并联,其等效电容为___。
A. 2μF
B. 3μF
C. 5μF
D. 6μF
【单选题】
瓷悬式绝缘子(抗拉)的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
钢化玻璃悬式绝缘子(抗拉)的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
瓷棒式绝缘子(抗弯)的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
针式绝缘子(抗弯)的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
钢筋混凝土支柱翼缘与横腹杆结合处裂纹宽度为___以下的可以使用。
A. 0.15mm
B. 0.2mm
C. 0.25mm
D. 0.3mm
【单选题】
检查火花间隙时,应用___兆欧表测绝缘电阻。
A. 500V
B. 1000V
C. 1500V
D. 2500V
【单选题】
棒式绝缘子弯曲度不得超过___。
A. 0.005
B. 0.01
C. 0.015
D. 0.02
【单选题】
定位器在平均温度时应垂直于线路中心线,当温度变化时,顺线路方向的偏移量应与接触线在该点随温度变化伸缩量相一致,其偏角最大不得大于___。
A. 15o
B. 18o
C. 20o
D. 22o
【单选题】
钢柱主角钢弯曲度不应大于___。
A. 1/500
B. 1/250
C. 1/200
D. 1/120
【单选题】
铜接触线在同一截面处损伤大于其截面___时,应截断重接。
A. 0.05
B. 0.08
C. 0.1
D. 0.12
【单选题】
承力索钢绞线7股中,断___及以上时,应截断重接。
【单选题】
道岔处两工作支接触线在间距___处应等高。
A. 300mm
B. 400mm
C. 500mm
D. 600mm
【单选题】
在限界门至铁路之间的公路两边各装设不少于___防护桩。
【单选题】
临时接地线应挂在接触网停电作业两端范围内,相距不得大于___。
A. 500m
B. 800m
C. 1000m
D. 1500m
【单选题】
铜合金接触线在最大允许磨耗面积20%的情况下,其机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
钢芯铝绞线承力索的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
铝包钢承力索的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
铜包钢承力索的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
铜绞线承力索的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
铜合金绞线承力索的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
电连接线应装在设计规定的位置,施工允许偏差为___。
A. ±0.3m
B. ±0.4m
C. ±0.5m
D. ±0.6m
【单选题】
三跨非绝缘锚段关节两转换柱间的两接触线水平间距为___。
A. 100mm
B. 200mm
C. 300mm
D. 500mm
【单选题】
合成材料绝缘元件(抗弯)的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 5.0
【单选题】
日光灯并联电容器的作用是___。
A. 改善电压
B. 提高功率因数
C. 便于启动
D. 分流
【单选题】
发电机右手定则,拇指是___。
A. 电势方向
B. 导线运动方向
C. 磁力线方向
D. 电流方向
【单选题】
直流电路中,若干电阻并联,流过每个电阻的电流与每个电阻值成___。
A. 正比
B. 反比
C. 不成比例
D. 相当
【单选题】
接触网静态检测中关节式分相的检测周期为___。
【单选题】
软横跨横向承力索中钢绞线的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
软横跨定位索的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
供电线的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
回流线的机械强度安全系数不应小于___。
A. 2.0
B. 2.5
C. 3.0
D. 4.0
【单选题】
在WORD的编辑状态,打开了“w1.doc”文档,把当前文档以“w2.doc”为名进行“另存为”操作,则___。
A. 当前文档是w1.doc
B. 当前文档是w2.doc
C. 当前文档是w1.doc与w2.doc
D. w1.doc与w2.doc全被关闭
【单选题】
接触线TCG-100的额定张力为___。
A. 10kN
B. 8.5kN
C. 15kN
D. 20kN
【单选题】
锚柱拉线应在线索下锚方向的延长线上,允许向田野侧偏差___。
A. 250mm
B. 300mm
C. 150mm
D. 200mm
【单选题】
回流线一般采用的线材为___。
A. 钢绞线
B. 钢芯铝绞线
C. 铝绞线
D. 镀铝锌钢绞线
【单选题】
两个电荷之间受力大小与距离的关系___。
A. 与距离成正比
B. 与距离成反比
C. 与距离平方成正比
D. 与距离平方成反比
【单选题】
力矩等于___。
A. 力乘以重量
B. 力乘以高度
C. 力乘力臂
D. 力乘以质量
【单选题】
接触线GLCA100/250的额定张力为___。
A. 10kN
B. 8.5kN
C. 15kN
D. 20kN
推荐试题
【多选题】
vSphere DRS helps to balance virtual machines with available resources in a vSphere cluster. What three types of resources can be taken into account for balancing? (Choose three.)___
A. CPU
B. physical NIC saturation of an ESXi host
C. virtual NIC saturation of a virtual machine
D. RAM
E. storage latency
【多选题】
Which three design requirements must be satisfied to enable RAID-6 objects in a VMware vSAN cluster? (Choose three.)___
A. vSAN Advanced license or higher
B. vSAN stretched cluster
C. at least six hosts contributing storage
D. deduplication and compression
E. all flash configuration
【多选题】
When using "Cluster resource percentage" for host failover capacity in vSphere HA Admission Control, the total resource requirements are calculated from which two values? (Choose two.)___
A. Total vCPUs assigned to each VM.
B. Average CPU usage on each VM over time.
C. Memory reservations on each VM.
D. Total memory assigned to each VM.
E. Average active memory on each VM over time.
F. CPU reservations on each VM.
【多选题】
Which are four attributes of the Active vCenter HA node? (Choose four)___
A. It uses the vCenter HA network to communicate with the Witness node.
B. It constantly replicates vPostgres data with the Witness node.
C. It uses a public IP address for the management interface.
D. It runs the active vCenter Server Appliance instance.
E. It uses the vCenter HA network for replication of data to the Passive node.
F. It provides a quorum to protect against split-brain situations.
【多选题】
Which are two vCenter Server two-factor authentication methods? (Choose two.)___
A. RSA SecurID
B. Smart Card
C. SAML
D. Symantec VIP
【多选题】
An administrator is creating VMkernel adapters on an ESXi 6.5 host and wants to create separate VMkernel adapters for every type of traffic in the default TCP/IP stack. Which three types of traffic can be explicitly enabled on a separate VMkernel adapter? (Choose three.)___
A. Virtual SAN traffic
B. NFS traffic
C. vMotion traffic
D. vSphere HA traffic
E. Fault Tolerance logging traffic
【多选题】
When migrating a Windows vCenter Server 6.0 to the vCenter Server Appliance 6.5, which two will be migrated by default? (Choose two.)___
A. Local Windows OS users and groups
B. Configuration
C. Custom ports
D. FQDN
E. Historical and Performance data
【多选题】
Which three types of Content Libraries exist within vSphere 6.5? (Choose three.)___
A. Remote Content Library
B. Published Content Library
C. Local Content Library
D. Shared Content Library
E. Subscribed Content Library
【多选题】
An administrator cannot enable multi-processor Fault Tolerance (SMP-FT) for a virtual machine. Which are two possible causes for this? (Choose two.)___
A. The virtual machine is running on a vSAN datastore.
B. The Fault Tolerance network is using a 10Gbit uplink.
C. The virtual machine has 6 vCPUs assigned.
D. The virtual machine has a 1TB VMDK attached.
E. The virtual machine has snapshots present.
【多选题】
Which two statements are true for Predictive DRS? (Choose two.)___
A. It balances resource utilization for virtual machines with unpredictable utilization patterns.
B. It integrates DRS with vRealize Operations Manager to balance workloads for virtual machines before resource utilization spikes occur.
C. It balances resource utilization based on a threshold's algorithm that runs each night.
D. It determines the best placement and balance of virtual machines based on a threshold's algorithm that runs each night in vCenter Server 6.5 Database.
【多选题】
Which two situations could cause a virtual machine to appear with (orphaned) appended to its name? (Choose two.)___
A. if a host failover is unsuccessful
B. if a virtual machine was removed from vCenter Server's inventory
C. if a virtual machine was deployed from template, and the template has been deleted
D. if a virtual machine is unregistered directly on the host
【多选题】
Which three requirements are needed to apply RAID 5 or RAID 6 erasure coding on a vSAN 6.2 or 6.5 object? (Choose three.)___
A. on Disk Format 3.0
B. Hybrid vSAN
C. All Flash vSAN
D. vSAN Advanced License
E. Stretched Cluster Configurations
【多选题】
An administrator sees the following error in the log files: Which two events could be the source of the error message? (Choose two.)___
A. vCenter Server failure
B. VXLAN failure
C. Disk array failure
D. Network failure
E. ESXi host failure
【多选题】
An administrator is attempting to access an ESXi host via the DCUI but is unable to do so. Which could be two possible causes? (Choose two.)___
A. The host in Qhas no out-of-band management capability (i.e. iLO/iDRAC).
B. The SSH service is disabled on the host.
C. Strict lockdown mode is enabled on the host.
D. Normal lockdown mode is enabled and the administrator is a member of the
E. xception User list.
【多选题】
Which two permissions are required to migrate a virtual machine with Storage vMotion? (Choose two.)___
A. Network > Move Network
B. Virtual Machine > Inventory > Move
C. Resource > Migrate powered on virtual machine
D. Datastore > Allocate Space
【多选题】
Which are three supported storage requirements for vCenter Server HA? (Choose three.)___
A. NFS
B. RDM
C. vSAN
D. VMFS
E. JBOD
【多选题】
Which are the two network requirements for a VMware vSAN 6.5 cluster? (Choose two.)___
A. Multicast must be enabled on the physical switches and routers that handle vSAN traffic.
B. vSAN requires IPv6 only.
C. All hosts must have a dedicated 40GbE NIC.
D. The vSAN network supported IPv4 or IPv6.
E. vSAN requires IPv4 only.
【多选题】
Which three prerequisites must be in place prior to enabling secure boot for a virtual machine? (Choose three.)___
A. VirtualMachine.Config.Settings privileges
B. an encrypted USB drive
C. Virtual Hardware version 13 or later
D. Virtual Hardware version 12 or later
E. EFI firmware
【多选题】
A user is given the "Virtual machine user (sample)" role in a vSphere 6.x environment. Which three permissions would the user be able to perform? (Choose three.)___
A. Reset a virtual machine.
B. Power on a virtual machine.
C. Move a host into a cluster.
D. Configure CD media.
E. Migrate a virtual machine with Storage vMotion.
【多选题】
Which three are supported upgrade processes for ESXi host? (Choose three.)___
A. using vSphere Auto Deploy
B. using a TFTP server
C. using Update Manager
D. using an
E. SXCLI command
【多选题】
When enabling Storage DRS on a datastore cluster, which three components are enabled as a result? (Choose three.)___
A. Space load balancing among datastore within the datastore cluster.
B. Initial placement for virtual disks based on space and I/O workload.
C. I/O load balancing among datastores within the datastore cluster.
D. Queue Depth alerting on disks within the datastore cluster.
E. Data de-duplication within the datastore cluster.
【多选题】
What are two features introduced in Network I/O Control version 3? (Choose two.)___
A. Bandwidth reservation per traffic type
B. Network resource pools
C. CoS tagging
D. Bandwidth guarantee to virtual machines
【多选题】
Which two correct virtual machine advanced configuration parameters will accomplish this? (Choose two.)___
A. isolation.device.edit.disable = “FALSE”
B. isolation.device.edit.disable = “TRUE”
C. isolation.device.connectable.disable = “FALSE”
D. isolation.device.connectable.disable = “TRUE”
【多选题】
Which three statements are correct regarding booting an ESXi Host from Fibre Channel SAN? (Choose three.)___
A. Direct connect topology is supported.
B. Each host must have its own boot LUN.
C. ESXi hosts do not require local storage.
D. Multipathing to a boot LUN on an active-passive array is supported.
E. Hosts can share one common boot LUN.
【多选题】
Which two tasks should a vSphere administrator perform if the vmkernel log reports VMFS metadata errors? (Choose two.)___
A. contact VMware technical support
B. reformat the datastore
C. check the device with VOMA
D. ignore the messages
【多选题】
Which two statements are true for a vCenterServer user account that is used for vSphere Data Protection (VDP)? (Choose two.)___
A. The user account must be assigned with Administrator role.
B. The password for the user account cannot contain spaces.
C. The user account should be created in the Single Sign-On domain
D. The user account cannot inherit required permissions from a group role.
【多选题】
Which three storage protocols are supported by Virtual Volumes? (Choose three.)___
A. FCIP
B. FCoE
C. iSCSI
D. NFS v3
E. NFS v4
【多选题】
A vSphere administrator observes a CPU spike on one of the web servers (view the Exhibit.) Which two statements can describe the cause of this activity? (Choose two.)___
A. The network packet size is too large.
B. VMware Tools is not installed.
C. Disk latency is present on the datastore.
D. The network packet size is too small.
【多选题】
Which three operations can cause VMFS metadata updates? (Choose three.)___
A. Restarting a VM using the guest OS.
B. Launching a VM console.
C. Migrating a VM with vMotion.
D. Powering a VM on or off.
E. Expanding a VMFS datastore.
【多选题】
*What two services run on all nodes in a vCenter Server HA cluster? (Choose two.)___
A. vmware-vmon
B. vmware-vpostgres
C. vmare-rbd-watchdog
D. vmware-vcha
【多选题】
Which two statements are true regarding Auto Deploy in version 6.5? (Choose two.)___
A. Auto Deploy can be configured and managed via PowerCLI.
B. Auto Deploy can be configured and managed via the vSphere Client.
C. Auto
D. eploy can be configured and managed via the vSphere Web Client.
【多选题】
What three options can improve network performance for a virtual machine? (Choose three.)___
A. MLD
B. TSO
C. NetFlow
D. LRO
E. SR-IOV
【多选题】
Which two storage technologies are supported for MSCS? (Choose two.)___
A. NFS
B. VAAI
C. iSCSI
D. FC
【多选题】
When upgrading a VMware vSAN cluster to version 6.5, which two tasks must be completed to comply with upgrade requirements and VMware-recommended best practices? (Choose two.)___
A. Use RVC to upgrade the hosts.
B. Use the latest available ESXi version.
C. Back up all VMs.
D. Use only the “Full data migration” maintenance mode option.
【多选题】
What two enhancements are in VMFS6 but not in VMFS5? (Choose two.)___
A. Support for 4k native disks
B. Support for 512e disks
C. GPT storage device partitioning
D. Automatic space reclamation
【多选题】
Which two statements describe why a vSphere DRS cluster would report load imbalance? (Choose two.)___
A. The configured migration threshold is too high.
B. The configured migration threshold is too low.
C. DRS is configured for Partially Automated.
D. Enhanced vMotion Compatibility (EVC) is enabled.
【多选题】
A vSphere Administrator must ensure that vCenter Server service is running in a domain user account rather than Local System Account. To accomplish this, the user account should have which two permissions? (Choose two.)___
A. Log on as a service.
B. Act as part of the operating system.
C. Log on as a batch job.
D. Log on locally.
【多选题】
A virtual machine fails to power on after being deployed from a template. What two remediation steps could correct this issue? (Choose two.)___
A. Increase CPU reservation
B. Decrease memory reservation
C. Increase memory reservation
D. Increase datastore capacity
E. Decrease CPU reservation
【多选题】
Which three directories are available under the vcsa-cli-installer folder of the vCenter Server Appliance installation media? (Choose three.)___
A. \mac
B. \ovftool
C. \migration-assistant
D. \win32
E. \lin64
【多选题】
What are three considerations when booting ESXihost from SAN software FCoE? (Choose three.)___
A. The VMware_FCoE_vSwitch that the installer automatically created cannot be changed.
B. Boot LUN cannot be shared with other hosts even on shared storage.
C. Multipathing is not supported at pre-boot.
D. Software FCoE boot configuration cannot be changed from within
E. SXi.