CLASS 7 PHYSICS Heat and Temperature

What unit is used to measure heat?

What is temperature a measure of?

What is the ice point on the Celsius scale?

What is the steam point on the Fahrenheit scale?

What is the normal body temperature of a healthy person in Celsius?

Why do telephone wires sag in the summer?

Why is a gap left between railway track rails?

Which of the following expands the most when heated to the same temperature?

What is heat transfer by direct contact called?

Which process involves heat transfer through the movement of fluids?

How does heat from the sun reach Earth?

Why is cork used in the walls of an oven?

Which of the following is a good insulator of heat?

Why is ice kept wrapped in a gunny bag during summer?

Why do we wear woolen clothes in winter?

In convection, the transfer of heat is always in which direction?

During the day, what is the breeze that blows from sea to land called?

What kind of clothes should we wear during summer season?

Why is there a vacuum between the walls of a thermos flask?

What happens to a substance when it is heated?

Why is it more effective to place a fan at the bottom of a room during cooling, rather than at the top?

A metal spoon is placed in a bowl of hot soup. Which process primarily causes the spoon to heat up?

Why do bridges often incorporate expansion joints in their design?

Consider two rods of equal length, one made of copper and the other of wood. If one end of each rod is heated, which rod will transfer heat more quickly to the other end?

Which of the following is the most important reason for using double-paned windows in cold climates:

Why does steam at 100°C cause more severe burns than water at 100°C?

A bimetallic strip is made of two different metals that expand at different rates when heated. How is this property utilized in thermostats?

If you were to touch a piece of metal and a piece of wood that are both at room temperature, the metal would feel colder. Why?

In a typical refrigerator, the cooling unit is located at the top. Why is this design choice more effective than placing it at the bottom?

Why do coastal areas experience milder temperatures compared to inland areas?

When a gas is compressed rapidly, its temperature usually increases. Why does this happen?

A dark-colored car gets hotter inside when parked in the sun compared to a light-colored car. Why?

Why is the air temperature often warmer on a cloudy night compared to a clear night?

Why do hot air balloons float?

If two objects of different temperatures are brought into contact, what determines the direction of heat flow between them?

Why are cooking pots often made with metal bottoms and insulated handles?

How does the concept of thermal expansion relate to the operation of a mercury thermometer?

Why does applying alcohol to the skin often produce a cooling sensation?

Certain compounds are formed at low temperatures more effectively than high temperatures. Why would this occur?

Explain how the design of a thermos flask minimizes heat transfer through conduction, convection, and radiation.

A blacksmith heats an iron ring to fit it onto a wooden wheel. Which property of thermal expansion is most crucial in this process?

Why are ventilators typically placed near the ceiling of a room?

Why does covering water pipes with cotton help prevent freezing in cold weather?

How does the vacuum layer in a thermos flask minimize heat transfer?

A metal bridge is constructed with one end on rollers. Why is this?

On a hot summer day, why does a sea breeze occur?

Consider two rooms, one painted white and the other black. If both rooms are exposed to the same amount of sunlight, which room will likely be cooler and why?

Why do gases expand more than solids or liquids when heated to the same temperature?

In the context of heat transfer, which scenario exemplifies radiation?

Why is ebonite used for the handles of tea kettles?

Heat is measured in units called Joules.

Temperature is a measure of how heavy an object is.

A thermometer is used to measure temperature.

The ice point on the Celsius scale is 100°C.

The upper fixed point is 212°F on the Fahrenheit scale.

0 K is the lowest possible temperature where no molecular motion occurs.

A healthy person's body temperature is about 47°C.

Telephone wires sag in winter due to expansion.

Iron rims are made smaller for wheel fitting and are heated to expand them.

A large gap is left between rails on a railway track.

Gas expands less than solids when heated to the identical temperature.

Conduction involves heat transfer through fluid movement.

Convection is the transfer of heat through electromagnetic waves.

Radiation can transfer heat through a vacuum.

Cork is a good conductor of heat.

Ebonite is a conductor of heat.

Wool keeps us warm in winter because it is a conductor of heat.

Convection transfers heat vertically upwards.

Sea breeze blows from land to sea during the day.

Dark clothes reflect sun's heat and keep our body cool.

A thermometer measures the quantity of heat in an object, typically recorded in Joules.

On the Fahrenheit scale, the interval between the ice point ($32°F$) and the steam point ($212°F$) is divided into 200 equal parts.

Telephone wires sag more in the winter due to the expansion of the metal caused by the colder temperatures.

Leaving gaps between cement floor pieces is intended to prevent cracking due to both expansion in the summer and contraction in the winter.

Gases expand less than solids when heated to the same temperature.

Conduction involves heat transfer through the movement of fluids, like when boiling water.

Radiation involves physical contact between two objects where heat flows from them

An oven is made of single walls with a vacuum in between filled with metal, as metal is a heat insulator, to ensure high temperature inside.

Ebonite is a conductor of heat, which makes it ideal for use in kettle handles, as this allows you to feel the temperature of the kettle's contents.

Wrapping ice in any bag will cause the ice to melt rapidly.

Air trapped in the fine pores of cotton or wool acts as a conductor of heat, which is why these materials help keep us warm or prevent water pipes from freezing.

The direction of heat transfer in convection is always horizontally left-to-right.

A ventilator placed near the floor is responsible for removing warm, impure air from a room.

Chimneys are provided over furnaces because the hot gases are denser and are pulled out, and air is pushed in.

During the day, land breezes blow from the sea to the land due to the land being cooler than the sea.

During night, sea cools down more faster than land, which causes the cold wind from sea blows toward the land to take its place.

In a refrigerator, the freezing chest is located at the bottom to cool the entire space since cold air rises.

Wearing dark colored clothes in summer can help reflect most of the sun's heat, thus keeping our body cool.

In a thermos flask, the vacuum between the walls prevents heat transfer exclusively by conduction, while the cork stopper only prevents heat transfer through radiation.

During thermal contraction the particles move faster and further apart.

If two objects at different temperatures are in thermal contact, heat will spontaneously flow from the colder object to the hotter object.

The Kelvin scale defines the ice point at 273 K and the steam point at 373 K, with each interval representing a degree of variable size compared to Celsius.

Substances contract when heated due to increased particle movement, resulting in particles moving closer together and decreasing volume.

Convection is the primary method of heat transfer through solids, relying on direct contact between objects.

In a thermos flask, the vacuum between the walls prevents heat transfer by conduction and convection, while the surfaces reduce transfer by radiation; the plastic stopper prevents transfer by convection.

Ebonite is a poor insulator of heat; therefore it is often used for the handles of tea kettles allowing for quicker heat transfer.

On the Fahrenheit scale, the interval between the ice point and the steam point is divided into 220 equal parts.

Black clothing is preferred in summer due to its ability to reflect heat, keeping the body cooler.

The functionality of a refrigerator depends upon the placement of the freezing chest at the bottom of the unit, promoting upward cool air convection patterns.

Land breezes occur during the day as land warms faster than the sea, causing air to rise and cold wind from the land to blow towards the sea.

[Blank] is the energy transferred from a hotter object to a colder one.

[Blank] is a measure of how hot or cold an object is.

A ______ is used to measure temperature.

On the Celsius scale, the ice point is ______ °C.

On the Fahrenheit scale, the ice point is ______ °F.

The body temperature of a healthy person is 37°C or ______ °F.

Telephone wires sag in summer because they ______ due to the rise in temperature.

[Blank] is the heat transfer through direct contact between objects.

[Blank] is the transfer of heat through the movement of a fluid.

[Blank] is the heat transfer through electromagnetic waves.

An oven is made of double walls with cork in between because cork is an ______ of heat.

Ebonite is an ______ of heat and used for kettle handles.

Woollen clothes keep us warm because both wool and air are ______ of heat.

The transfer of heat is always vertically upwards in the process of ______.

During the night, a land breeze blows from ______ to sea.

During the day, a sea breeze blows from sea to ______.

White clothes ______ most of the sun's heat.

The ______ present between the walls of a thermos flask prevents transfer of heat by conduction and convection.

[Blank] is the energy transferred from a hotter object to a colder one and is measured in Joules.

A ______ is used to measure how hot or cold an object is.

On the Fahrenheit scale, the ice point is 32°F and the ______ point is 212°F.

A small gap is left between successive rails on a railway track to allow for ______ of the rails during summer.

The air filled in the fine pores of a gunny bag is an ______ of heat, preventing ice from melting rapidly.

[Blank] clothes have fine pores filled with air, and both wool and air are insulators of heat, keeping us warm in winter.

During summer near the sea, a breeze blows from land to sea at night, known as a ______ breeze.

The freezing chest in a refrigerator is fitted near the top to facilitate ______ currents that cool the entire space.

We prefer to wear ______ or light-coloured clothes in summer because they reflect most of the sun's heat.

The vacuum between the walls of a thermos flask prevents heat transfer by ______ and convection.

The shining surface on the outer side of the inner wall of a thermos flask reduces heat transfer by ______.

When a substance is cooled, its particles slow down and move closer together, leading to thermal ______.

Different materials conduct heat at different ______.

[Blank] generally transfer heat through conduction, while liquids and gases transfer heat through convection.

The normal body temperature for a healthy person is 37°C, which is equivalent to ______°F.

Ebonite is an insulator of heat, so tea kettles are provided with an ebonite ______.

Chimneys are provided over furnaces in factories so that hot gases, being less dense, rise up and come out through the ______.

The temperature scale where the interval between the ice point and steam point is divided into 180 equal parts is the ______ scale.

In the context of heat transfer, the method that relies on electromagnetic waves to transfer heat through a vacuum is known as ______.

The reason telephone wires sag more in the summer than in the winter is due to thermal ______ caused by the increase in temperature.

The effectiveness of woollen clothing in winter is primarily due to the trapped air within its fibers, which acts as a heat ______, preventing heat loss from the body.

The functioning of a Thermos flask relies on minimizing heat transfer through conduction, convection, and ______ to keep its contents at a stable temperature.

In coastal regions, the phenomenon where a breeze blows from the land to the sea during the night is known as a ______ breeze, a result of convection processes.

The Kelvin scale marks absolute zero as 0 K, representing the temperature at which all molecular ______ theoretically ceases.

The design of bridges often incorporates rollers under one end of the steel girders to accommodate thermal ______ and prevent damage to the bridge's structure.

In refrigerators, the freezing chest is typically located at the top to facilitate ______ currents, which aid in cooling the entire compartment efficiently.

Unlike solids and liquids, gases exhibit a greater degree of thermal ______ when heated to the same temperature, due to the weaker inter-molecular forces.

What unit is heat measured in?

What is the name of the device used to measure temperature?

What is the temperature of the ice point on the Celsius scale?

What is the temperature of the steam point on the Fahrenheit scale?

What is considered the normal body temperature of a healthy person in Celsius?

What is the process of heat transfer through direct contact?

What type of heat transfer involves the movement of fluids?

What type of heat transfer can occur through a vacuum?

Name a material that is a good insulator of heat.

Why are gaps left between rails on a railway track?

Does gas expand more or less compared to solids when heated to the same temperature?

What is the lowest possible temperature on the Kelvin scale?

What kind of clothes should we wear in summer?

What type of breeze blows from land to sea during the night?

What process causes sea and land breezes?

Do solids transfer heat through conduction, convection, or radiation?

What is thermal expansion?

What is thermal contraction?

Explain how the design of a thermos flask minimizes heat transfer.

Why are gaps left between successive rails on a railway track?

Explain why telephone wires sag more in the summer than in the winter.

Describe how a sea breeze is formed during the day.

Explain why the freezing compartment in a refrigerator is located at the top.

Why do we typically wear light-colored clothes in summer?

Describe how heat is transferred when you stir hot coffee with a metal spoon.

Explain how a hot air balloon works, referencing heat transfer concepts.

Why are cooking pots often made with metal bottoms and plastic or wooden handles?

Describe the process of how heat from the sun reaches the Earth.

Explain why steam at 100°C causes more severe burns than water at 100°C.

How does a bimetallic strip work in a thermostat, referencing the properties of thermal expansion?

Explain why ice is often wrapped in a gunny bag to prevent it from melting quickly.

How does the concept of convection contribute to the formation of land breezes at night?

Explain the function of chimneys in factories in terms of heat transfer.

Describe how woollen clothing helps to keep us warm in winter, relating to the concept of heat insulators.

Explain why bridges often have steel girders placed on rollers at one end.

Explain why the handles of tea kettles are often made of ebonite or another insulating material.

Explain why cement floors are laid in small pieces with gaps in between.

Explain why bridges often incorporate expansion joints. How do these joints mitigate potential damage from temperature fluctuations, and what type of heat transfer is most relevant to this consideration?

Describe how a bimetallic strip works in a thermostat, focusing on the properties of the two metals involved and their response to changes in temperature. Which of the heat transfer methods is the most influential on its function?

Explain why coastal areas often experience milder temperature variations compared to inland regions. In your explanation, describe how water's unique thermal properties influence this phenomenon, with regards to heat transfer.

A blacksmith heats a metal horseshoe before shaping it. Describe the changes occurring at the microscopic level within the metal as its temperature increases, and how this relates to the blacksmith's ability to manipulate the metal more easily.

Explain why a metal railing feels colder to the touch than a wooden bench, even when both are at the same ambient temperature. What property of the materials accounts for this difference, and what mode of heat transfer is most involved?

Describe how a solar oven works, detailing the principles of heat transfer involved in cooking food using only sunlight. Consider conduction, convection, and radiation in your explanation.

Explain why a double-paned window is more effective at insulating a house than a single-paned window. Specifically address the role of the air gap between the panes in minimizing heat transfer.

Explain how a hot air balloon works, focusing on the relationship between temperature, air density, and buoyancy. How does the process of convection contribute to the balloon's ability to float?

Describe how clothing helps us stay warm, especially in cold weather. What properties of the materials used in clothing contribute to insulation, and how do they minimize heat loss from our bodies?

Discuss the implications of thermal expansion in the design and construction of pipelines that transport hot fluids over long distances. What engineering solutions are employed to address the challenges posed by expansion and contraction?