Question

Two statements are given. One labelled Assertion " A" and the other labelled Reason" R".Select the correct answer to the question from the codes (a) , (b) , (c) ,(d)
Assertion "A": Alloys are commonly used in electrical heating devices like electrical iron and toaster.
Reason (R) : Resistivity of an alloy is generally higher than that of its constituent metals but alloys have low melting point than their constituent metals. 
A)Both (A) and (R) are true and (R) is the correct explanation of the assertion 
B)Both (A) and (R) are true but (R) is not the correct explanation of the assertion 
C)(A) is true but (R) is false
 D)(A) is false but (R) is true​

Answer 1

Explanation:

In this question, we have to study the assertion and it's reason. First of all, we will check that they are correct and then R is the correct explanation of A or not. So let's check them:

Assertion:

Alloys are commonly used in electrical heating devices like electrical iron and toaster.

The alloys are combination of metals and some non-metals. They have high resistance to the flow of current and hence a lot of heat is released in this process. They resist the flow of current. Due to this phenomenon of release of heat, they are used for heating devices like Heater or toaster. So, assertion is correct✓

Reason:

Resistivity of an alloy is generally higher than that of its constituent metals but alloys have low melting point than their constituent metals.

As we already knew that, alloys are made up of different metals and non-metals, the arrangement of ions inside them. The high restivity is due to crystal lattice. And we know that metals have high meting point but other metals and non-metals mixed with them act as their impurities and hence restrict high melting point. Thus, alloy have low melting point. We have seen this in cases of fuse. So, reason is correct✓.

━━━━━━━━━━━

Now we can see that the assertion and reason, both are correct and also the reason is explaining the assertion well because alloys are used for high restivity and low melting point in electrical heaters and toasters.

So, the correct option is:

$\huge{ \boxed{ \sf{ \purple{Option \: A}}}}$

And we are done !!

Answer 2

Answer:

Question:-

One labelled Assertion " A" and the other labelled Reason" R".Select the correct answer to the question from the codes (a) , (b) , (c) ,(d) .

Assertion "A": Alloys are commonly used in electrical heating devices like electrical iron and toaster.

Reason (R) : Resistivity of an alloy is generally higher than that of its constituent metals but alloys have low melting point than their constituent metals. 

Answer:-

★ A)Both (A) and (R) are true and (R) is the correct explanation of the assertion.

Explanation:-

Assertion- Alloys are commonly used in electrical heating devices like electric iron and heater. Reason- Resistivity of an alloy is generally higher than that of its constituent metals but the alloys have low melting points than their constituent metals. ... So it has partial characteristics of metal and non metal.

Reason:-

Alloys are used in electrical heating devices rather than pure metals because the resistivity of an alloy is more than the resistivity of a pure metal. Moreover alloy does not burn (or oxidize) easily even at higher temperature A an R are true and R is the correct explanation of the assertion.