Home
Class 11
PHYSICS
If vec A xx vec B= vec C xx vec B, show ...

If `vec A xx vec B= vec C xx vec B`, show that `vec C` need not be equal to vec A`.

Text Solution

Verified by Experts

` vec A xx vec B= vec C xx vec B or vec A xxx vec B -vec C xxx vec B=0`
or ` (vec A-vec C) xxx vec B=0` …(i)
To satisfy (i), the three possibilities can be there
(i) `vec A -vec C` =0 or `vec A =vec C`
(ii) ` vec B= vec 0`
(iii) ` vec A-vec C and vec B` are parallel to each other i.e. `vec A--vec C=n vec B`, wher (n) a non zeroreal number.
or `vec A = vec C + n vec B`
Thus, if ` vec A xx vec B =vec C xx vec B, vec C` need not be equal to `vec A`. The given statement is true if ` vec B`
is a zero vector of `vec A` is equal to vec C + n vec B`.
Promotional Banner

Topper's Solved these Questions

  • KINEMATICS

    PRADEEP|Exercise 4 Conceptual Problems|1 Videos
  • KINEMATICS

    PRADEEP|Exercise 4 Con ceptual Problems|22 Videos
  • KINEMATICS

    PRADEEP|Exercise 2 Con ceptual Problems|15 Videos
  • GRAVIATION

    PRADEEP|Exercise Assertion-Reason Type Questions|19 Videos
  • LAWS OF MOTION

    PRADEEP|Exercise Assertion- Reason Type Questions|17 Videos

Similar Questions

Explore conceptually related problems

If vec A xx vec B=vec A xx vec C , is it correct to conclude that vec B =vec C ?

If three vectors vec A, vec B and vec C are such that vec A .vec B =vec A .vec C , vec A xx vec B = vec A xx vec C , vec A!= vec 0 then prove that vec B =vec C .

If vec a ,\ vec b ,\ vec c are three vectors such that vec adot\ vec b= vec adot\ vec c and vec a\ xx\ vec b= vec a\ xx\ vec c ,\ vec a\ !=0 , then show that vec b= vec c .

If vec A, vec B and vec C are vectors such that | vec B | - | vec C | * Prove [(vec A + vec B) xx (vec A + vec C)] xx (vec B + vec C) * (case B + case C) = 0

If vec(a) xx vec(b)= vec(c) xx vec(d) and vec(a) xx vec(c) =vec(b) xx vec(d)," show that " (vec(a)- vec(d)) " is parallel to " (vec(b)-vec(c)) , it being given that a !=d and b != c.

Fven that vec A xx vec B= vec B xx vec C = vec 0 . If vec A. vec B and vec C are not null vectors, find the value of vec Cxx vec A .

Let vec a xx vec b,vec b xx vec c,vec c xx vec a are non coplanar vectors and [[vec a,vec b,vec c]]=1.vec r is a vector such that vec r.vec a=vec r.vec b=vec r.vec c=2, then area of triangle whose vertices are vec a,vec b and vec c is (A) |vecr|/2 (2) 2|vecr| (C) |vecr|/4 (D) 4|vecr|

Let veca = hati - 2 hatj + 2hatk and vec b = 2 hati - hatj + hatk be two vectors. If vec c is a vector such that vecb xx vec c = vec b xx vec a and vec c vec a = 1 , then vec c vec b is equal to :

Let lambda = vec a xx (vec b + vec c), vec mu = vec b xx (vec c + vec a) and vec nu = vec c xx (vec a + vec b). Then

[[vec a + vec b-vec c, vec b + vec c-vec a, vec c + vec a-vec b is equal to

PRADEEP-KINEMATICS-3 Con ceptual Problems
  1. Two vectors vec(a) and vec(b) are such that |vec(a)+vec(b)|=|vec(a)-ve...

    Text Solution

    |

  2. The three vectors vec A, vec B and vec C are repesented in magnitude a...

    Text Solution

    |

  3. Show that the displacement vector does not depend upon the choece of t...

    Text Solution

    |

  4. ABCD is a parallelogram Fig. 2 (c ) .64. AC and (BD) are its diagonals...

    Text Solution

    |

  5. The greatest resultant of two vectors vec P and vec Q is (n) times the...

    Text Solution

    |

  6. ABCDEF is a regular hexagon, Fig. 2 (c ) .65. What is the value of ...

    Text Solution

    |

  7. Can a rectangular component of a vector be greater than the vector its...

    Text Solution

    |

  8. Can a flight of a bird be an example of composition of vectors ?

    Text Solution

    |

  9. A room has dimensions 3 m xx 4 m xx5 m. A fly starting at one cronet e...

    Text Solution

    |

  10. A vecto vec A has magnitude 2 and another vector vec B has magnitude 3...

    Text Solution

    |

  11. A man directly crosses a river in time t1 and swims down the current a...

    Text Solution

    |

  12. An aeroplane takes off at an angle or 30^(@) to the horizontal. If the...

    Text Solution

    |

  13. A plane is travlling eastward at a speed of 400 km h^)-1) . Wind is b...

    Text Solution

    |

  14. A weight mg is suspended from the middle of a rope whose ends are at t...

    Text Solution

    |

  15. If vec A. vec B = vec A. vec C, is it correct to conclude that vec B ...

    Text Solution

    |

  16. Three vector vec(A),vec(B), vec(C ) satisfy the relation vec(A)*vec(B)...

    Text Solution

    |

  17. If vec A xx vec B=vec A xx vec C, is it correct to conclude that vec B...

    Text Solution

    |

  18. If vec A xx vec B= vec C xx vec B, show that vec C need not be equal t...

    Text Solution

    |

  19. If three vectors vec A, vec B and vec C are such that vec A .vec B =...

    Text Solution

    |

  20. In an Delta ABC as showin in Fig. 2 . (2) .71 (a) prove that a/(sin...

    Text Solution

    |