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Dot product of two vectors overset(rarr)...

Dot product of two vectors `overset(rarr)A` and `overset(rarr)B` is defined as `overset(rarr)A.overset(rarr)B=AB cos phi` , where `phi` is angle between them when they are drawn with tails coinciding. For any two vectors . This means `ovsert(rarr)A . overset(rarr)B=overset(rarr)B. overset(rarr)A` that . The scalar product obeys the commutative law of multiplication, the order of the two vectors does not matter. The vector product of two vectors `overset(rarr)A` and `overset(rarr)B` also called the cross product, is denoted by `overset(rarr)A xx overset(rarr)B` . As the name suggests, the vector product is itself a vector. `overset(rarr)C=overset(rarr)A xx overset(rarr)B` then `C=AB sin theta` ,
For non zero vectors `overset(rarr)A, overset(rarr)B, overset(rarr)C,|(overset(rarr)Axxoverset(rarr)B).overset(rarr)C|=|overset(rarr)A||overset(rarr)B||overset(rarr)C|` holds if and only if

A

`overset(rarr)A.overset(rarr)B=0,overset(rarr)B.overset(rarr)C=0`

B

`overset(rarr)B.overset(rarr)C=0,overset(rarr)C.overset(rarr)A=0`

C

`overset(rarr)C.overset(rarr)A=0,overset(rarr)A.overset(rarr)B=0`

D

`overset(rarr)A.overset(rarr)B=overset(rarr)B.overset(rarr)C=overset(rarr)C.overset(rarr)A=0`

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The correct Answer is:
To solve the problem, we need to analyze the given expression involving the cross product and the dot product of vectors. Let's break it down step by step. ### Step 1: Understand the Given Expression We have the expression: \[ |(\overset{\rarr}{A} \times \overset{\rarr}{B}) \cdot \overset{\rarr}{C}| = |\overset{\rarr}{A}| |\overset{\rarr}{B}| |\overset{\rarr}{C}| \] This expression states that the magnitude of the dot product of the vector resulting from the cross product of vectors A and B with vector C equals the product of the magnitudes of vectors A, B, and C. ### Step 2: Expand the Left Side The left side can be expanded using the definition of the cross product and the dot product: \[ \overset{\rarr}{C} = \overset{\rarr}{A} \times \overset{\rarr}{B} \] The magnitude of the cross product is given by: \[ |\overset{\rarr}{A} \times \overset{\rarr}{B}| = |\overset{\rarr}{A}| |\overset{\rarr}{B}| \sin \phi \] where \(\phi\) is the angle between vectors A and B. Now, we can write: \[ |(\overset{\rarr}{A} \times \overset{\rarr}{B}) \cdot \overset{\rarr}{C}| = |\overset{\rarr}{A} \times \overset{\rarr}{B}| |\overset{\rarr}{C}| \cos \theta \] where \(\theta\) is the angle between the vector \((\overset{\rarr}{A} \times \overset{\rarr}{B})\) and vector C. ### Step 3: Set Up the Equation Substituting the expression for the magnitude of the cross product into the equation gives: \[ |\overset{\rarr}{A}| |\overset{\rarr}{B}| \sin \phi |\overset{\rarr}{C}| \cos \theta = |\overset{\rarr}{A}| |\overset{\rarr}{B}| |\overset{\rarr}{C}| \] ### Step 4: Simplify the Equation We can cancel out the common terms (assuming none of the vectors are zero): \[ \sin \phi \cos \theta = 1 \] ### Step 5: Analyze the Condition The equation \(\sin \phi \cos \theta = 1\) implies: 1. \(\sin \phi = 1\) and \(\cos \theta = 1\) From \(\sin \phi = 1\), we find that: \[ \phi = 90^\circ \] This means that vectors A and B are perpendicular to each other. From \(\cos \theta = 1\), we find that: \[ \theta = 0^\circ \] This means that vector C is parallel to the vector resulting from the cross product of A and B. ### Step 6: Conclusion Thus, for the expression to hold true, we conclude that: - Vectors A and B are perpendicular (\(\phi = 90^\circ\)). - Vector C is parallel to the vector resulting from the cross product of A and B (\(\theta = 0^\circ\)). ### Final Answer The condition holds true if and only if: - \(\overset{\rarr}{A} \perp \overset{\rarr}{B}\) and \(\overset{\rarr}{C} \parallel (\overset{\rarr}{A} \times \overset{\rarr}{B})\).

To solve the problem, we need to analyze the given expression involving the cross product and the dot product of vectors. Let's break it down step by step. ### Step 1: Understand the Given Expression We have the expression: \[ |(\overset{\rarr}{A} \times \overset{\rarr}{B}) \cdot \overset{\rarr}{C}| = |\overset{\rarr}{A}| |\overset{\rarr}{B}| |\overset{\rarr}{C}| \] This expression states that the magnitude of the dot product of the vector resulting from the cross product of vectors A and B with vector C equals the product of the magnitudes of vectors A, B, and C. ...
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Dot product of two vectors overset(rarr)A and overset(rarr)B is defined as overset(rarr)A.overset(rarr)B=aB cos phi , where phi is angle between them when they are drawn with tails coinciding. For any two vectors . This means overset(rarr)A . overset(rarr)B=overset(rarr)B. overset(rarr)A that . The scalar product obeys the commutative law of multiplication, the order of the two vectors does not matter. The vector product of two vectors overset(rarr)A and overset(rarr)B also called the cross product, is denoted by overset(rarr)A xx overset(rarr)B . As the name suggests, the vector product is itself a vector. overset(rarr)C=overset(rarr)A xx overset(rarr)B then C=AB sin theta , overset(rarr)A=hat i+ hat j-hatk and overset(rarr)B=2 hat i +3 hat j +5 hat k angle between overset(rarr)A and overset(rarr)B is

Dot product of two vectors overset(rarr)A and overset(rarr)B is defined as overset(rarr)A.overset(rarr)B=aB cos phi , where phi is angle between them when they are drawn with tails coinciding. For any two vectors . This means overset(rarr)A . overset(rarr)B=overset(rarr)B. overset(rarr)A that . The scalar product obeys the commutative law of multiplication, the order of the two vectors does not matter. The vector product of two vectors overset(rarr)A and overset(rarr)B also called the cross product, is denoted by overset(rarr)A xx overset(rarr)B . As the name suggests, the vector product is itself a vector. overset(rarr)C=overset(rarr)A xx overset(rarr)B then C=AB sin theta , A force overset(rarr)F=3hat i +c hat j + 2 hatk acting on a particle causes a displacement d=4hat i- 2 hat j + 3 hat k . If the work done (dot product of force and displacement) is 6J then the value of c is :

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VMC MODULES ENGLISH-INTRODUCTION TO VECTORS & FORCES -level 2
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  2. The angle between vector (overset(rarr)Axxoverset(rarr)B) and (overset...

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  3. Dot product of two vectors overset(rarr)A and overset(rarr)B is defi...

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  4. Dot product of two vectors overset(rarr)A and overset(rarr)B is defi...

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  5. Dot product of two vectors overset(rarr)A and overset(rarr)B is defi...

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  6. Maximum and minimum values of the resultant of two forces acting at a ...

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  7. A force ( 3 hati +4 hat j) newton acts on a body and displaces it by...

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  8. If a vector 2 hat (i) + 3 hat(j) + 8 hat(k) is perpendicular to the ve...

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  9. What is the torque of a force overset(rarr)F=(2 hat i -3 hat j +4 hat ...

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  10. The magnitudes of the X and Y components of overset(rarr)P are 7 and...

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  11. A car is going in south with a speed of 5m//s. To a man sitting in car...

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  12. The area of parallelogram represented by the vectors overset(rarr)A =...

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  13. The river 500 m wide is flowing with a current of 4kph. A boat starts ...

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  14. An aeroplane takes off from Mumbai to Delhi with velocity 50 kph at an...

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  15. If the system is in equilibrum, find the Normal Reaction between 2kg a...

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  16. The string and the pulley are massless and the system is in equilibriu...

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  17. The block is always at rest, the maximum force which can be applied fo...

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  18. A force of 200N is applied as shown in the figure on block of 3 kg. Th...

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  19. A river is flowing with a velocity of 2m/s. If the width of river in 1...

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  20. A force 3hat i+4 hat j - 5 hatk N is acting on a particle. If the ve...

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