Question

8) A metallic rectangular cuboid of dimensions
4 cm x 6 cm x 8 cm is melted and some more
metal is added to make it a cube, the measure
of whose side is an integer. What is the
minimum volume of metal to be added and
what is the side of the cube?


Answer :-
Dimensions of cuboid are 4cm X 6cm X 8cm.

Volume of a cuboid = Length \times× Width \times× Height

So, volume of given cuboid = 4 \times× 6 \times× 8 = 192 cm^3cm3

It is given that the cuboid is converted to a cube.
Volume of cube = (Side)^{3}(Side)3

It is given that some minimum volume is added to cuboid to make cube whose side is an integer.

If we have a look at the perfect cube integers, cube nearest to 192 is 216.

So, Minimum volume of metal to be added = 216 - 192 = 24 cm^3cm3

Also, Volume of cube = (Side)^{3}(Side)3
216 = (Side)^{3}(Side)3

\Rightarrow \text{Side = 6 cm}⇒Side = 6 cm

So, minimum volume of metal to be added is 24 cm^3cm3 and side of cube is 6 cm.
​

Answer 1

Chemical weathering typically increases as temperatures rise and rain falls, which means rocks in hot and wet climates experience faster rates of chemical weathering than do rocks in cold, dry climates.

Physical weathering occurs more often in cold climates, because the different minerals within rocks expand and contract at different rates when they are heated and cooled. Repeated heating and cooling cycles eventually cause rocks to fracture. Desert and mountain climates experience a wide range of temperatures from low to high during a day and night, which accounts for the breakdown of rocks known as physical weathering.

Biological weathering occurs when living organisms break up rocks. Tree roots, for example, can fracture rocks in the same way they buckle pavement. Warm, humid climates are most favorable to life. Contrast the rich diversity of life in a rainforest, for example, with the scarcity of life in the dry Sahara or the frigid Antarctic. Consequently, rates of biological weathering are most rapid in warm humid climates like those in tropical regions.

Answer 2

Answer:

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Step-by-step explanation:

आकाश में इंद्रधनुष बारिश के समय में ही क्यों दिखाई देता है इसका वैज्ञानिक कारण भी है। ... सूर्य के प्रकाश के पानी की बूंदों में पड़कर बिखरने की यह प्रक्रिया प्रकाश के अपवर्तन तथा परावर्तन के रूप में जानी जाती है, इसके परिणामस्वरूप ही हमें सात रंगों वाला इंद्रधनुष दिखाई देता है।