Year 8 Electrical Energy Storage - Batteries

The role or purpose of the battery in a circuit is to ____. Choose three.

• supply electric charge so that a current can exist

• supply energy to the charge

• move the charge from the - to the + terminal of the battery

• transform energy from electrical energy into light energy

• establish an electric potential difference between the + and - terminals

Answer explanation

To establish an electric circuit, charge must be moved from low energy to high energy. Once at high energy, the charge spontaneously flows through the conducting wires and other conducting elements of the circuit back down to the low energy terminal. A battery's role is to supply the energy which is required to move the charge from the - terminal to the + terminal of the battery. By placing a large quantity of like charge at one location, an electric pressure or potential difference is established, forcing the like charges to move away from this location to the location of opposite charge (the - terminal).

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

A battery is needed in the circuit of your flashlight so that ____.

• charge is provided to the wires

• the energy of the light is balanced by the battery

• an exothermic, light-creating reaction is possible

• an electric potential difference is maintained across the circuit

Answer explanation

One of the roles of a battery is to simply establish a difference in electric potential between its two terminals. Charge at the high potential will flow through the external circuit to the low potential location.

If an electric circuit was analogous to a water park, then the battery would be analogous to the ____.

• the change in potential energy of the riders

• the people which flow from the top of the water ride to the bottom of the water ride

• pump which supplies energy to move the water from the ground to a high elevation

• the long lines which exist at the park

• i. the speed at which riders move as they slide from the top to the bottom of the ride

Answer explanation

A water ride at a water park is analogous to an electric circuit. First of all, there is an entity which flows - water flows in a water park and (in conventional terms) + charge flows in an electric circuit. In each case, the fluid flows spontaneously from a high energy location to a low energy location. The flow is through pipes (or slides) in a water park and through wires in an electric circuit. If the pipes or the wires are broken, then there can be no continuous flow of fluid through the circuit. A complete loop is required to establish the circuit.

This flow of fluid - whether of water or charge - is possible when a pressure difference is created between two locations in the circuit. In the water park, the pressure difference is the difference in water pressure created by two locations of different heights. Water flows spontaneously from locations of high pressure (high altitude) to locations of low pressure (low altitude). In an electric circuit, the electric potential difference between the two terminals of a battery or energy source provides the electric pressure which presses on charge to move them from a location of high pressure (high electric potential) to a location of low pressure (low electric potential).

Energy is required to move the fluid uphill. In a water park, a water pump is used to do work upon the water in order to raise it from the low height back up to the high height. The water pump does not supply the water; the water which is already in the pipes. Rather, the water pump supplies the energy to pump the water from the location of low energy and low pressure to the location of high energy and high pressure. In an electric circuit, the battery is the charge pump which pumps the charge through the battery from the location of low electric potential energy (the - terminal) to the location of high electric potential energy (the + terminal). The battery does not supply the electric charge; the charge is already in the wires. The battery simply supplies the energy to do work on the charge in pumping it uphill.

Tags

NGSS.MS-PS3-5

 If an electric circuit was analogous to a water park, then the electric current would be analogous to the ____.

• pipes which carry the water through the water circuit

• pump which supplies energy to move the water from the ground to a high elevation

• the rate at which water is pumped onto the slide

• the long lines which exist at the park

• the change in potential energy of the riders

Answer explanation

The flow of water at a water park is analogous to the flow of charge in an electric circuit. The rate at which charge moves past a point on a circuit as measured in Coulombs of charge per second (or some comparable set of units) is known as the  current. In our analogy, the fluid which flows is water and the rate at which the fluid passes any given point is the current.

9. If an electric circuit was analogous to a water park, then the positive terminal of the battery would be analogous to the ____.

• the top of the water slide

• the people which flow from the top of the water ride to the bottom of the water ride

• the long lines which exist at the park

• the speed at which riders move as they slide from the top to the bottom of the ride

Answer explanation

A water ride at a water park is analogous to an electric circuit. First of all, there is an entity which flows - water flows in a water park and (in conventional terms) + charge flows in an electric circuit. In each case, the fluid flows spontaneously from a high energy location to a low energy location. The flow is through pipes (or slides) in a water park and through wires in an electric circuit. If the pipes or the wires are broken, then there can be no continuous flow of fluid through the circuit. A complete loop is required to establish the circuit.

This flow of fluid - whether of water or charge - is possible when a pressure difference is created between two locations in the circuit. In the water park, the pressure difference is the difference in water pressure created by two locations of different heights. Water flows spontaneously from locations of high pressure (high altitude) to locations of low pressure (low altitude). In an electric circuit, the electric potential difference between the two terminals of a battery or energy source provides the electric pressure which presses on charge to move them from a location of high pressure (high electric potential) to a location of low pressure (low electric potential).

Energy is required to move the fluid uphill. In a water park, a water pump is used to do work upon the water in order to raise it from the low height back up to the high height. The water pump does not supply the water; the water which is already in the pipes. Rather, the water pump supplies the energy to pump the water from the location of low energy and low pressure to the location of high energy and high pressure. In an electric circuit, the battery is the charge pump which pumps the charge through the battery from the location of low electric potential energy (the - terminal) to the location of high electric potential energy (the + terminal). The battery does not supply the electric charge; the charge is already in the wires. The battery simply supplies the energy to do work on the charge in pumping it uphill.

Charge flowing through this circuit is most energized at ____. Choose the one best answer.

• the + terminal of the battery

• the - terminal of the battery

• just prior to entering the light bulb

• ... nonsense! The energy of the charge is the same everywhere throughout the circuit.

Two or more of the following words and phrases mean the same thing. Identify them by listing their letters.

• a. Voltage

• b. Wattage

• c. Electric Potential Difference

• e. Electric Pressure

• Energy

Answer explanation

The voltage or electric potential difference are synonymous terms. Voltage is not synonymous with energy. While voltage (or electric potential difference) is a measure of how energized a quantity of charge is at a given location, voltage is expressed as the energy per charge (and not simply as energy). Drawing from the analogy between a water park and an electric circuit, voltage is a measure of the quantity of electric pressure placed upon a charge in inducing it to move from one location to another location.

Wattage is synonymous with power. Current is synonymous with the rate at which charge flows.

What is the flow of electricity known as?

• Flow of electrons

• electric current

• an epic fail

• a series circuit

Which of the following is used to measure the amount of energy per second in the current?

• elecmeter

• voltmeter

• ammeter

• switch

Another name for a battery is a cell?

• true

• false