JEE MAIN - Physics (2021 - 27th July Morning Shift - No. 11)
Assertion A : If A, B, C, D are four points on a semi-circular are with centre at 'O' such that $$\left| {\overrightarrow {AB} } \right| = \left| {\overrightarrow {BC} } \right| = \left| {\overrightarrow {CD} } \right|$$, then $$\overrightarrow {AB} + \overrightarrow {AC} + \overrightarrow {AD} = 4\overrightarrow {AO} + \overrightarrow {OB} + \overrightarrow {OC} $$
Reason R : Polygon law of vector addition yields $$\overrightarrow {AB} + \overrightarrow {BC} + \overrightarrow {CD} + \overrightarrow {AD} = 2\overrightarrow {AO} $$
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In the light of the above statements, choose the most appropriate answer from the options given below :
Reason R : Polygon law of vector addition yields $$\overrightarrow {AB} + \overrightarrow {BC} + \overrightarrow {CD} + \overrightarrow {AD} = 2\overrightarrow {AO} $$
In the light of the above statements, choose the most appropriate answer from the options given below :
A is correct but R is not correct.
A is not correct but R is correct.
Both A and R are correct and R is the correct explanation of A.
Both A and R are correct but R is not the correct explanation of A.
توضیح
Polygon law is applicable in both but the equation given in the reason is not useful in explaining the assertion.