Gibilisco: Chapter 7 - Cells And Batteries! MCQs Quiz

A primary cell is a type of cell that cannot be recharged. Unlike secondary cells, which can be recharged multiple times, primary cells are designed for single use and once their energy is depleted, they cannot be recharged. Examples of primary cells include alkaline batteries and zinc-carbon batteries.

The 12-V auto battery is rated at 36 Ah, which means it can provide a current of 36 Amps for 1 hour. The 100-W, 12-Vdc bulb will draw a current of 100/12 = 8.33 Amps. Dividing the battery capacity (36 Ah) by the current drawn by the bulb (8.33 Amps), we get approximately 4.32 hours. Therefore, the bulb will stay lit for about 4 hours and 20 minutes before the battery is fully discharged.

A direct short-circuit of a battery can cause an explosion because it creates a pathway with very low resistance for the current to flow. This leads to a rapid and excessive discharge of energy, causing the battery to overheat and potentially explode. Short-circuits bypass the internal protection mechanisms of the battery, allowing a high current to flow uncontrollably, which can result in a dangerous release of energy.

Mercury cells and batteries are considered disadvantageous because they pollute the environment. Mercury is a toxic substance that can contaminate soil, water, and air if not disposed of properly. This pollution can have harmful effects on ecosystems and human health. Therefore, it is important to handle and dispose of mercury-containing cells and batteries responsibly to minimize their environmental impact.

An electronic calculator would be the best power-source choice for a transistor battery because calculators require low power consumption and a small, compact power source. Transistor batteries are small and provide a stable power supply, making them ideal for powering electronic calculators.

Connecting solar cells in parallel increases the current from a solar panel. When solar cells are connected in parallel, the current produced by each cell adds up, resulting in a higher overall current output. This is because the voltage across each cell remains the same, but the current is divided among the cells. As a result, the total current is increased, making parallel connection an effective way to increase the current from a solar panel.

A Weston cell is generally used as a voltage reference source. A Weston cell is a type of electrochemical cell that produces a stable and accurate voltage. It consists of a cadmium electrode and a mercury amalgam electrode in a saturated cadmium sulfate solution. The cell generates a constant voltage of 1.0186 volts, which remains stable over time. This makes it ideal for calibrating and measuring voltages in various electrical and electronic devices.

A flat discharge curve means that the cell or battery maintains a constant current-delivering capability until it dies. This indicates that the voltage output remains relatively stable throughout the discharge process. It is a desirable characteristic as it allows for a more accurate estimation of the remaining battery life and ensures a consistent power supply until the end.

The chemical energy in a battery or cell is converted into kinetic energy when the cell is used. This conversion occurs as a result of the chemical reactions happening within the battery, which produce an electric current. Once the chemical energy is used up, it cannot be replenished, indicating that it cannot be sustained or restored. Therefore, the correct answer is that the chemical energy changes to kinetic energy when the cell is used.

A "lantern" battery is typically used to power devices that require a large amount of energy for an extended period of time, such as a two-way portable radio. It is unlikely to be found in a heart pacemaker, electronic calculator, or LCD wall clock, as these devices typically require smaller and less powerful batteries.

An interactive solar power system allows a homeowner to sell power to the utility. This means that when the solar panels generate excess electricity, the homeowner can feed it back into the grid and receive credits or payment from the utility company. This feature enables homeowners to not only generate their own electricity but also contribute to the overall energy supply.

Methanol is easier to transport and store compared to hydrogen. This is because hydrogen is a gas and requires specialized storage and transportation infrastructure, such as high-pressure tanks or cryogenic containers. Methanol, on the other hand, is a liquid at room temperature and can be easily stored and transported using conventional methods, like tanks or barrels. This advantage makes methanol a more practical and feasible option for fuel cells, as it simplifies the logistics and reduces the costs associated with handling and distributing the fuel.

The given answer, 733 mAh, is the correct unit for measuring the amount of charge supplied by the cell. The question states that the cell supplies a current of 100 mA for a duration of seven hours and twenty minutes. To calculate the charge supplied, we can use the formula Q = I * t, where Q is the charge, I is the current, and t is the time. Plugging in the values, we get Q = 100 mA * 7.33 hours = 733 mAh. Therefore, the cell has supplied 733 mAh of charge.

Alkaline cells are generally better in radios than zinc-carbon cells because they have a higher energy density, which means they can provide more power and last longer. This is especially important in devices like radios that require a consistent and reliable power source. Additionally, alkaline cells have a lower internal resistance, allowing them to deliver power more efficiently, resulting in better performance in radios.

The energy in a cell or battery depends mainly on its physical size because the size determines the amount of active material present in the cell, which directly affects the energy storage capacity. A larger physical size allows for more active material, which can store more energy. The current drawn from the cell and its voltage also play a role in determining the energy output, but they are not the main factors.

A lithium battery would most likely be chosen for a microcomputer memory backup because lithium batteries have a high energy density, which means they can store a large amount of energy in a small and lightweight package. This makes them ideal for applications where space and weight are limited, such as in microcomputers. Additionally, lithium batteries have a long shelf life and can retain their charge for extended periods of time, making them reliable for backup power in case of a power outage or when the main power source is unavailable.

A lead-acid battery is commonly used in devices that require a high amount of power for extended periods of time, such as portable video cameras/recorders. These batteries are known for their ability to provide a consistent and reliable source of power, making them suitable for devices that need to operate for long durations. Therefore, it is most likely to find a lead-acid battery in a portable video camera/recorder rather than in a portable audio cassette player, an LCD wall clock, or a flashlight.

Nickel-cadmium batteries should never be used until they "die" because they have a memory effect. This means that if they are consistently recharged before being fully discharged, they will gradually lose their maximum capacity. To maintain their optimal performance, it is recommended to discharge nickel-cadmium batteries completely before recharging them.

Making an extremely high-voltage battery of cells would be impractical because there is no real need for it. This suggests that the demand for such a high-voltage battery is low or non-existent. Therefore, it would not be cost-effective or efficient to manufacture and use such a battery.

The voltage in a battery is more than the voltage in a cell of the same kind because a battery is made up of multiple cells connected together in series or parallel. Each cell produces a certain voltage, and when multiple cells are combined, their voltages add up. Therefore, the voltage of a battery is greater than that of a single cell.

A NICAD battery, short for nickel-cadmium battery, is commonly used in various electronic devices due to its high energy density and long cycle life. It is often found in portable devices like portable cassette players and handheld radio transceivers, as well as in satellites. Therefore, the correct answer is "In more than one of the above" as NICAD batteries can be found in multiple types of devices.