Science - Grade 4 - Semester 1

Science - Grade 4 - Semester 1

by Marijana Knezevic

Energy, Speed, and Moving Objects​

​energy 能量 : The ability to do work or to cause change.

motion 运动 : The act or process of moving or the way something moves.

potential energy 势能 : The energy that comes from how an object is positioned, bent, stretched, or compressed.

kinetic energy 动能 : The energy of a moving object, depending on its mass and how fast it is moving.

speed 速度 : The distance an object travels in a particular amount of time; described as fast or slow.

transfer 传递，transform 转换， vehicle safety engineer 汽车安全工程师， form of energy 能量的形式，particle 微粒

​Collisions

​collision 碰撞 : The action that occurs when one object bumps into another object.

​transfer 传递 : The process in which energy moves from one object to another.

transform 转换 : The process in which energy changes from one kind to another.

​Energy Transfer

heat 热量 : The transfer of thermal energy from one object to another.

thermal energy 热能 : Energy that an object has because of the movement of its particles.

wave 波 : A form of the transfer of energy

​light 光 : A form of energy that we can see.

​radiation 辐射 : Energy that travels as a

wave.

sound 声 : Energy in the particles that vibrate as they pass through matter.

particle 微粒

Multiple Choice

·      Potential energy is the energy an object has due to its:

• Position

• Motion

• Temperature

• Atomic structure

Multiple Choice

·      When does an object have no kinetic energy?

• When it’s at rest

• When it’s moving slowly

• When the only force that is acting on it is gravity

• When it has no electrical charge

Multiple Choice

·      Which object has the most potential energy?

• A ball resting on the ground

• A ball being thrown at 100 miles per hour

• A ball on top of a refrigerator

• A ball resting on the edge of a cliff

Multiple Choice

·      What are two main forms of energy?

• Kinetic energy and potential energy

• Kinetic energy and electricity

• Potential energy and wind energy

•   Potential energy and electricity

Multiple Choice

·      What is energy? Choose the best answer.

• Anything that radiates light or heat

• Anything that travels in the form of a wave

• Any object in motion

• Anything that can cause change

Multiple Choice

·      The Sun is a source of __________ energy.

• Potential

• Electrical

• Mechanical

• Light

Multiple Choice

·      What happens when a cold drink sits in a hot room?

• It remains cold

• It gets warmer

• It starts boiling

• It starts freezing

Multiple Select

·      Which one of the following requires kinetic energy? Choose more than one answer.

• Sleeping

• Swimming

• Turning a doorknob

• Listening to music

• Hitting a tennis ball

Multiple Choice

·      Kinetic energy is energy an object has because of its __________.

• composition

• position

• density

• motion

Multiple Choice

·      Which of the following objects has kinetic energy?

• A bowling ball resting on the ground

• A bowling ball lifted of the ground

• A car driving down the road

• A car parked on the street

Electric Circuits​

​electric current 电流 : The flow of charged particles in the same direction.

electricity 电 : A form of energy that can be carried by wires and is used to provide power, made available by the flow of electric charges.

electric circuit 电路 : A complete path in which electric currents flow.

electric charge 电荷 : A property that causes matter to have an electric force when it is placed near other charged matter.

conductor 导体 : A material that allows an electric current to flow through it.

insulator 绝缘体 : A material that does not allow an electric current to flow through it.

battery 电池，rub 摩擦， bulb 电灯泡，holder 底座， flow 流动，wire 电线，金属丝

Energy Conversion​

energy conversion 能量转换 : The process in which energy change from one kind to another, also known as energy transformation.

fuel 燃料 : A material that releases energy as heat when it burns.

combustion 燃烧 : The process of burning a fuel to produce heat and light.

chemical energy 化学能 : Energy stored in fuels; it comes from a chemical change.

petroleum 石油， copper strip 铜片，natural gas 天然气， electrical engineer 电气工程师，burn 燃烧， renewable 可再生的，device 设备，coal 煤， nonrenewable 不可再生的，zinc strip 锌片

​Nonrenewable Energy Sources

​nonrenewable 不可再生的 : A material that is not made fast enough to replace what is used.

oil 油 : A thick liquid that is found in rock underground.

fossil fuel 燃料 : A material which is formed as ancient plants and animals decayed underground.

coal 煤 : A hard, black substance which chemical changes transformed plant stems and leaves into.

​​Nonrenewable Energy Sources

​petroleum 石油 : A liquid fossil fuel formed by the decay of ancient plants and animals.

natural gas 天然气 : A fossil fuel that occurs in the gas state and was formed by the decay of ancient plants and animals.

nuclear fuel 核燃料 : The unstable elements that produce nuclear energy in power plants.

uranium 铀 : A chemical element, a heavy, silver-white, radioactive metal used mainly in producing nuclear energy.

​Renewable Energy Sources

​renewable 可再生的 : A material that is made by nature at least as quickly as people use it.

solar energy 太阳能 : Energy from the sun being used directly or changed to electrical energy.

geothermal energy 地热能 : Heat energy obtained from beneath the earth's surface.

wind energy 风能 : Energy of moving air that can be changed to electrical energy by wind turbines.

hydropower 水力发电 : Using the energy of moving water.

Multiple Choice

·      What is an example of a non-renewable energy source?

• Sunlight

• Oil

• Wind

• Biomass

Multiple Choice

·      Which of the following is true about nonrenewable energy sources?

• They took thousands of years to form.

• They do not need to be conserved.

• They will never run out.

• All the above.

Multiple Choice

·      _______________ energy sources cannot be replaced quickly.

• Renewable

• Nonrenewable

Multiple Choice

·      Which of the following is NOT a fossil fuel?

• Natural Gas

• Electricity

• Oil

• Petroleum

Multiple Choice

·      Coal, oil, and natural gas are easy to use but __________ the air.

• conserve

• pollute

Multiple Choice

·      _______________ is an energy that cannot be replaced easily once it is used.

• Renewable Energy Resource

• Nonrenewable Energy Resource

• Fossil Fuels

• Forever Fuels

Multiple Choice

·      What state of matter is oil?

• solid

• liquid

• gas

Multiple Choice

·      The burning of fossil fuels causes the earth to warm more quickly because of greenhouse gasses and pollution.

• True

• False

Multiple Choice

·      This type of renewable energy converts the power of the wind to electricity.

• Steam engines

• Wind turbines

• Solar power

• Nuclear power

Multiple Choice

·      Hydroelectric plants perform which type of energy conversion?

• Water to Electricity

• Electricity to Water

• Wind to Electricity

• Wind to Chemical

​

​

​Environmental Impacts of Energy Use

​pollutant 污染物 : A harmful substance that can poison lands, water, and air.

greenhouse gas 温室气体 : A pollutant that increases the atmosphere's ability to hold heat.

emission 排放 : The release of substances into the environment.

​Properties of Waves

​wave 波 : A disturbance that carries energy and travels in a repeated pattern.

vibration 振动 : Quickly move back and forth about a point; it may have a pattern.

medium 介质，中间物 : A substance between objects through which waves can travel.

amplitude 振幅 : The greatest height of a wave from its resting position.

wavelength 波长 : The distance between similar points on a wave.

frequency 频率 : The number of wave repetitions in a certain amount of time.

​Patterns of Waves

​wave period 波的周期 : The amount of time it takes for a wave to complete one back-and-forth motion.

circular wave 圆形波 : A wave that is caused by a disturbance at a single point.

plane wave 平面波 : A wave that is made when a line of matter is disturbed.

​Waves and Electromagnetic Spectrum

​ray 射线 : A line of energy that continues in one direction until it hits an object.

reflect 反射 : To bounce off a surface and move in a new direction.

refract 折射 : To bend when entering a new medium.

absorb 吸收 : To take in; when light hits an object but is not reflected or bent, it is absorbed.

system 系统 : A group of parts that work together as a whole.

white light 白光 : Light such as sunlight that contains all the visible colours.

opaque 不透光的 : The property of letting no light through.

transparent 透光的 : The property of letting almost all light through.

translucent 半透光的 : The property of letting some light through.

Multiple Choice

·      A harmful substance that can poison lands, water and air is called?

• Sunlight

• Oil

• Wind

• Pollutant

Multiple Choice

·      The number of wave repetitions in a certain amount of time is called __________.

• Wave

• Frequency

• Amplitude

• Medium

Multiple Choice

·      When light hits an object, but it is not reflected or bent, it is absorbed. To absorb means __________.

• to take in

• to take out

Multiple Choice

·      A greenhouse gas is a pollutant that increases the atmosphere’s ability to hold ______.

• cold

• heat

• water

• sun

Multiple Choice

·      Opaque matter lets _______ light through.

• some

• no

• almost all

• all the above

Multiple Choice

·      Translucent matter lets ______ light through.

• some

• no

• almost all

• all the above

Multiple Choice

·      Transparent matter lets ______ light through.

• some

• no

• almost all

• all the above

Multiple Choice

·      Carbon Dioxide is always produced by _____________.

• emission

• amplitude

• combustion

• wind