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How is the metal rim fixed on the wooden wheel of a cart? The metal rim is made slightly smaller than the wooden wheel. On heating, the rim expands and fits onto the wheel. Cold water is then poured over the rim, which contracts and fits tightly onto the wheel.
How can a small rim be fixed into a large wheel?
Metal Rim of wooden wheel is made smaller in size because, when it is heated it expands and becomes bigger than the Wooden Wheel. when this expanded Metal Rim is put over the Wooden Wheel and Cold Water is poured over it, The Metal Rim has a Tight Fitting.
Why the size of iron rim that is fixed on a wooden wheel is little less than the wooden wheel?
Iron rims are made smaller than wooden wheels. When the iron rim is heated, it expands and will have the same size as wooden wheels. When water is poured, the rims become cool and get compressed. Thus it can take the shape of the wooden wheel and gets fixed on the wheels firmly.
Why are metal rims heated to fix them onto the wooden wheels?
A blacksmith heats the metal rim to fix it onto a cart wheel because a metal rim is made slightly smaller. On heating, the rim expands and fits onto the wheel. Then on cooling, the rim contracts and fits tightly onto the wheel.
What changes occur when heating a metal rim?
on heating a metal rim the metal rim expands. this is because the the molecules of the metal start moving away from each other. this causes the metal rim to expand.
What type of change is used for fixing a metal rim to a wooden wheel of a cart?
The metal rim gets heated to fix it on to a cart because metal rims are made slightly smaller. On heating, the rim expands and fits on to the wheel. Then on cooling, the rim contracts and fits slightly on to the wheel. It is a physical process.
Which method is used to cover the wooden wheels of bullock carts with iron rims?
Answer: Heating. The wooden wheels of a bullock cart are covered with iron rims by heating them in the first place as they get expanded upon heating. They are then cooled down rapidly so that they easily fit on to the wheel.
What happens when an iron rim is heated for Class 6?
Answer: On heating, metals undergo expansion and contract to their original size on cooling. On heating the metal rim, it expands and then it is fixed on to the wooden wheel. After cooling, metal rim contracts and gets fixed firmly to the wooden wheel.
How does a blacksmith fix an iron rim around a wooden wheel?
To fit the ring on the wheel, it is heated so that its temperature rises by ΔT and it just steps over the wheel. As it cools down to surrounding temperature, it presses the semicircular parts together.
What happens when metal is heated?
Metal expands when heated. Length, surface area and volume will increase with temperature. The scientific term for this is thermal expansion. Thermal expansion occurs because heat increases the vibrations of the atoms in the metal.
When iron blade is fixed to wooden handle it is heat a by heating then cooling B by cooling then heat C by cooling d by freezing?
Heating of the blade leads to its expansion and thus the ring gets bigger. This happens because metals always expand on heating. The metal bladw is then fitted easily into the wooden handle. After this, cold water is usually poured on the iron blade which leads to the contraction of the expanded iron blade.
How the expansion of metal which is a reversible change put to good use?
Ans: The expansion of metals is a reversible change and its good use can be expressed by an example below: Iron rims are mounted on wooden cart wheels. To start with the Iron rims are slightly smaller than the wooden wheel. The iron rim is heated when its size becomes larger than the wooden wheel.
Why are small holes made in iron blade where a wooden handle is fixed?
Iron blade of tools has a ring in which the wooden handle is fixed. Normally the ring is slightly smaller in size than wooden handle. To fix handle ring is heated and it expands. hence, the hole in spade is slightly smaller than the size of wooden handle.
Why is the iron rim heated to red hot before mounting it on a wooden wheel?
They are heated red hot before fixing them on the cart wheels to expand them so that they can be easily fixed on the wheels and water is poured on them to cool them. As the rims cool they contract and take the shape of the wheel and get firmly fixed on the wheels.
Why iron rims are heated before putting them on the wheels of bullock carts?
Answer: The iron ring to be put on the rim of a cart wheel is always of slightly smaller diameter than that of the wheel. When the iron ring is heated to become red hot, it expands and slips on to the wheel easily. When it is cooled, it contracts and grips the wheel firmly.
How does the metal rim get fixed on the wooden wheel explain the two changes that take place during this process?
Iron rim is slightly smaller in size. This rim is then heated and the rim expands. After that some water is poured over it to cool down the iron. After cooling down, iron rim shrinks and fixes around the wooden wheel.
Why iron tools are heated before fixing them into their handles?
Metal tools are heated to expend the opening where the handle is inserted . once heated, the handle is inserted and the metal contracts to make a tight fit keeps the head from flying off and punching through the windshield.
How is wooden handle fixed in the ring of the iron tool?
Answer: To fix the handle, the ring is heated and it becomes slightly large in size. Then, the handle easily fits into the ring. When the ring cools down, it contracts and fits tightly onto the handle.
Why does a blacksmith heat the metal rim to fix it on a car wheel?
A blacksmith heats the metal rim to fix it onto a cart wheel because a metal rim is made slightly smaller. On heating, the rim expands and fits onto the wheel. Then on cooling, the rim contracts and fits tightly onto the wheel.
Why tools are often heated before fixing wooden handles?
The iron blade of soil digging tools has a ring in which the wooden handle is fixed. To fix the handle, the ring is heated and it becomes slightly larger in size (expands). Therefore, the handle easily fits into the ring. When the ring cools down, it contracts and fits tightly on to the handle.
How is it possible to fit the metal rim over a cart wheel tightly?
Ans: Metal rim is made slightly smaller than the wooden wheel. On heating rim expands and fits into wheel. Cold water is then poured over rim, which contracts and fits tightly onto the wheel.
What is an irreversible change?
A change is called irreversible if it cannot be changed back again. In an irreversible change, new materials are always formed. Sometimes these new materials are useful to us.
