2.5.7 Practice Questions

Which of the following statements about cleaning monitors and display devices is true?

A monitor should be powered off and cleaned with a lint-free cloth.

Your company provides testing services that help customers identify and resolve performance issues with their software and e-commerce sites before they go live. To perform accurate testing, a large number of computers are required, sometimes numbering in the hundreds. Recently, you have noticed that the lights in the testing lab seem dimmer than normal and sometimes flicker. Which of the following electrical terms BEST describes the condition you are most likely experiencing?

Brownout The dimming or flickering is most likely caused by a drop in the voltage to the lab due to the large number of computer being run at the same time. This drop in voltage is known as a brownout and can be harmful to your computers. You should take steps to maintain a constant level of electricity. Power surges (also called power spikes) are abnormally high voltages that last for short periods of time. These can also be harmful to your computers. A blackout is the total loss of power.

Which of the following device types should be plugged into a surge-protected-only outlet on a UPS unit, and not a battery backup outlet?

Laser printer Due to the periodic high power requirements to heat the fuser roller, a laser printer should not be plugged into a UPS's battery backup outlets. Instead, a laser printer should only be plugged into the surge protection outlets or directly into a wall outlet. Inkjet printers, external hard drives, and secondary LED monitors should be plugged into battery backup outlets.

A new laptop was delivered to your home and left on the porch while you were at work. It is very cold outside, and you don't know how long it has been there. You unpack the computer. You would like to know if it is working properly. Which of the following is the BEST action to take?

Let the computer warm up to room temperature before turning it on. If a computer has been in a cold environment, you should let it warm up to room temperature before turning it on. Otherwise, the heat produced by the components might cause water condensation inside the computer. This water might then damage system components. However, placing the laptop next to a heater set on high would be a poor strategy for warming the system up because it could potentially melt the plastic parts within the unit. Blowing compressed air into the cooling ports will not warm up the laptop.

Which of the following are common tools used to physically clean the inside of a computer? (Select TWO.)

Natural bristle brush Compressed air You can use a natural bristle brush and can of compressed air to blow dust off of a motherboard and other circuit cards. Never use anything harsh, such as a wire brush. Rags are also discouraged because they easily snag on electrical leads and parts.

Which of the following features should you look for when selecting a vacuum cleaner for your cleaning kit? (Select TWO).

One that blows as well as vacuums: Non-static generating It is important to select a vacuum cleaner for use with computer equipment that will not generate harmful static. Electrostatic discharge should always be avoided around sensitive computer components. In some cases, it may be better to remove dust and other foreign matter by applying a blowing force rather than vacuuming. The bag used in this type of vacuum should be fine enough to collect toner particles. Otherwise, these particles may circulate within and outside the vacuum and spread toner.

Besides protecting a computer from under-voltages, a typical UPS also performs which other actions? (Select TWO.)

Protects from over-voltages Conditions the power signal A typical UPS protects a computer from overvoltages as well as undervoltages. Also, because the quality of the electrical signal provided by a UPS battery is not as good as the AC power from the wall outlet, UPS devices often have built-in line conditioners.

Which of the following devices help protect equipment from temporary, above-normal voltages?

Surge Protector A power surge is a temporary, excessive voltage increase to a computer. A surge protector helps protect hardware from power surges. A power strip may or may not include surge protection circuits. An ESD grounding strap should be worn when touching anything inside a computer to avoid shocking computer components by not sharing a common ground.

What does occasional beeping from the UPS mean?

The computer is running on the UPS battery power Most UPS manufacturers indicate AC power outages and internal battery use with occasional beeping, usually about four beeps every 30 seconds. Some UPS units have a switch that you can use to disable the warning signal when running on battery power. Other types of beeps, such as rapid chirping or beeps at more frequent intervals, indicate other UPS problems. A failed connection between the UPS and the computer or a low battery on the UPS would most likely provide a visual notification on the computer screen from the UPS monitoring software, not an audible beep.

Your company resides in an area with rapid growth in both the corporate and residential areas surrounding your office. As such, your company has been experiencing several brownouts due to power grid problems (too much demand and not enough electricity). Fearing that your computers (especially the servers) could be damaged by these brownouts, your manager has asked you to find a solution to this problem. Which of the following would be the BEST device to recommend to your manager for computer protection?

UPS An uninterruptible power supply (UPS) is a device that contains a large battery suitable to run the attached devices for an extended period of time in the event that power is lost or drops below an acceptable level. A UPS can protect your computers from brownouts, power surges, and blackouts. UPSs can be purchased in varying size to accommodate large server or individual computers. A surge suppressor is typically a small box with several utility outlets, a power switch, and a three-wire cord for plugging into a wall outlet. The purpose of this device is to protect the electrical devices plugged in the suppressor from voltage spikes or power surges. A surge suppressor will not protect equipment from a drop in voltage. A ground-fault circuit interrupter (GFCI) is a protection device designed to protect people from electric shock from an electrical system. A GFCI protects you from ground faults (such as an electrical short). You often see these outlets in bathrooms and kitchens, where the chance of an electrical shock is greater due to water. A power strip can sometimes include a surge suppressor, but often only provides a way to plug multiple appliances into on wall outlet.

You are trying to help a co-worker order a UPS for each PC in her remote office location. What rating is used to specify the size of a UPS?

VA The size of a UPS is specified by a volt-amp (VA) rating. The larger the VA rating of the UPS, the longer the UPS can keep the system running in the event of a power failure. Volts are only part of the rating system used for UPS units. Ohms are not used to rate UPS units, nor is wattage.

Which of the following is most helpful in keeping a computer cool? (Select TWO).

Verify that cooling fans are not circulating air in the wrong directions. Vacuum dust from the system regularly. Vacuuming dust from the system is critical to keeping the computer cool. In addition, verify that your cooling fans are blowing air in the right direction and are not working against each other. Do not remove any slot covers in an attempt to cool the computer. Lacking slot covers decreases the fan's ability to remove hot air from inside the computer.