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The angle between vector (overset(rarr)A...

The angle between vector `(overset(rarr)Axxoverset(rarr)B)` and `(overset(rarr)B xx overset(rarr)A)` is :

A

zero

B

`pi`

C

`pi/2`

D

`pi/4`

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The correct Answer is:
To find the angle between the vectors \( \vec{A} \times \vec{B} \) and \( \vec{B} \times \vec{A} \), we can follow these steps: ### Step 1: Understand the Cross Product The cross product of two vectors \( \vec{A} \) and \( \vec{B} \) is defined as: \[ \vec{A} \times \vec{B} = |\vec{A}| |\vec{B}| \sin(\theta) \hat{n} \] where \( \theta \) is the angle between the vectors \( \vec{A} \) and \( \vec{B} \), and \( \hat{n} \) is a unit vector perpendicular to the plane formed by \( \vec{A} \) and \( \vec{B} \). ### Step 2: Determine the Direction of the Cross Products 1. The vector \( \vec{A} \times \vec{B} \) will be directed according to the right-hand rule, which gives a direction perpendicular to both \( \vec{A} \) and \( \vec{B} \). 2. Conversely, the vector \( \vec{B} \times \vec{A} \) will point in the opposite direction, since: \[ \vec{B} \times \vec{A} = -(\vec{A} \times \vec{B}) \] ### Step 3: Analyze the Relationship Between the Two Cross Products From the above, we can conclude: \[ \vec{B} \times \vec{A} = -(\vec{A} \times \vec{B}) \] This means that the vector \( \vec{B} \times \vec{A} \) is in the exact opposite direction of \( \vec{A} \times \vec{B} \). ### Step 4: Calculate the Angle Between the Two Vectors The angle \( \phi \) between two vectors \( \vec{C} \) and \( \vec{D} \) can be calculated using the dot product: \[ \cos(\phi) = \frac{\vec{C} \cdot \vec{D}}{|\vec{C}| |\vec{D}|} \] However, since \( \vec{D} = -\vec{C} \), we have: \[ \vec{C} \cdot \vec{D} = \vec{C} \cdot (-\vec{C}) = -|\vec{C}|^2 \] Thus: \[ \cos(\phi) = \frac{-|\vec{C}|^2}{|\vec{C}| |\vec{D}|} = -1 \] This implies that: \[ \phi = 180^\circ \text{ or } \pi \text{ radians} \] ### Conclusion The angle between the vectors \( \vec{A} \times \vec{B} \) and \( \vec{B} \times \vec{A} \) is \( \pi \) radians.

To find the angle between the vectors \( \vec{A} \times \vec{B} \) and \( \vec{B} \times \vec{A} \), we can follow these steps: ### Step 1: Understand the Cross Product The cross product of two vectors \( \vec{A} \) and \( \vec{B} \) is defined as: \[ \vec{A} \times \vec{B} = |\vec{A}| |\vec{B}| \sin(\theta) \hat{n} \] where \( \theta \) is the angle between the vectors \( \vec{A} \) and \( \vec{B} \), and \( \hat{n} \) is a unit vector perpendicular to the plane formed by \( \vec{A} \) and \( \vec{B} \). ...
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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 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

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 :

If overset(rarr)B=noverset(rarr)A and overset(rarr)A is antiparallel with overset(rarr)B , then n is :

ABCDEF is regular hexagon with point O as centre. The value of overset(rarr)AB+overset(rarr)AC+overset(rarr)AD+overset(rarr)AE+overset(rarr)AF = n xx overset(rarr)AO is . Find n.

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