Home
Class 11
PHYSICS
The line of action of a force vec(F)=(-3...

The line of action of a force `vec(F)=(-3hat(i)+hat(j)+5hat(k)) N` passes through a point `(7, 3, 1)`. The moment of force `(vec(tau)=vec(r)xxvec(F))` about origin is given by

A

`14hat(i)+38hat(j)+16hat(k)`

B

`14hat(i)+38hat(j)-16hat(k)`

C

`14hat(i)-38hat(j)+16hat(k)`

D

`14hat(i)-38hat(j)-16hat(k)`

Text Solution

Verified by Experts

The correct Answer is:
C
`vec(tau)=vec(r)xxvec(F)=|(hati,hatj,hatk),(7,3,1),(-3,1,5)|=14hat(i)-38hat(j)+16hat(k)`
Promotional Banner

Topper's Solved these Questions

  • MISCELLANEOUS

    ALLEN|Exercise Exercise-03|1 Videos

  • MISCELLANEOUS

    ALLEN|Exercise Exercise-04|1 Videos

  • MISCELLANEOUS

    ALLEN|Exercise Exersice -05(B)|20 Videos

  • KINEMATICS (MOTION ALONG A STRAIGHT LINE AND MOTION IN A PLANE)

    ALLEN|Exercise BEGINNER S BOX-7|8 Videos

  • PHYSICAL WORLD, UNITS AND DIMENSIONS & ERRORS IN MEASUREMENT

    ALLEN|Exercise EXERCISE-IV|8 Videos

Similar Questions

Explore conceptually related problems

A force vec(F) = 4hat(i) + 3hat(j) - 2hat(k) is passing through the origin. Its moment about point (1,1,0) is

A force vec(F)=3hat(i)+2hat(j)-4hat(k) is applied at the point (1, -1, 2) . Find the moment of vec(F) about the point (2, -1, 3) .

A force vec(F) = 3 hat(i) + 2hat(j) - 4hat(k) is applied at the point (1, -1, 2) . What is the moment of the force about the point (2 , -1, 3) ?

A force vec(F)=4hat(i)+hat(k) acts through point A (0, 2, 0). Find the moment vec(m) of vec(F) about the point B (4, 0, 4).

If vec(F) = (5hat(i)+2hat(j) - 4hat(k))N , the magnitude of force is

The torque of a force vec(F)=-2hat(i)+2hat(j)+3hat(k) acting on a point vec(r )=hat(i)-2hat(j)+hat(k) about origin will be

The torque of force vec(F)=-3hat(i)+hat(j)+5hat(k) acting at the point vec(r)=7hat(i)+3hat(j)+hat(k) is ______________?

The torque of force F = -3 hat(i)+hat(j) + 5 hat(k) acting on a point r = 7 hat(i) + 3 hat(j) + hat(k) about origin will be

What is the magnitude of the moment of the couple consisting of the force vec(F)=3 hat(i)+2hat(j)-hat(k) acting through the point hat(i)-hat(j)+hat(k) and -vec(F) acting through the point 2hat(i)-3hat(j)-hat(k) ?

If vec(a)=hat(i)-2hat(j)+5hat(k) and vec(b)=2hat(i)+hat(j)-3hat(k) then what is (vec(b)-vec(a)). (3vec(a)+vec(b)) equal to ?

ALLEN-MISCELLANEOUS-Exercise-02
  1. Following forces start acting on a particle at rest at the origin of t...

    Text Solution

    |

  2. Which of the following group have the same dimensions.

    Text Solution

    |

  3. The line of action of a force vec(F)=(-3hat(i)+hat(j)+5hat(k)) N passe...

    Text Solution

    |

  4. A particle moves so that its position vector is given by vec r = cos o...

    Text Solution

    |

  5. The magnitude of scalar product of two vectors is 8 and of vector prod...

    Text Solution

    |

  6. Force acting on a particale is (2hat(i)+3hat(j))N. Work done by this f...

    Text Solution

    |

  7. Equation of line BA is x+y=1. Find a unit vector along the reflected r...

    Text Solution

    |

  8. The vector (vec(a)+3vec(b)) is perpendicular to (7 vec(a)-5vec(b)) and...

    Text Solution

    |

  9. Forces proportional to AB , BC and 2 CA act along the slides of a tria...

    Text Solution

    |

  10. A charges cork of mass m suspended by a light stright is placed in uni...

    Text Solution

    |

  11. A charged particle having some mass is resting in equilibrium at a hei...

    Text Solution

    |

  12. The charge per unit length of the four quadrant of the ring is 2 lambd...

    Text Solution

    |

  13. The figure shows a nonconducting ring which has positive and negative ...

    Text Solution

    |

  14. A circular ring carries a uniformly distributed positive charge .The e...

    Text Solution

    |

  15. Find the force experienced by a semicircular rod having a charge q as ...

    Text Solution

    |

  16. Which of the following is true for the figure showing electric lines o...

    Text Solution

    |

  17. An electric charge 10^(-8) C is placed at the point (4m, 7m, 2m). At t...

    Text Solution

    |

  18. Two point charges Q and - Q //4 are separated by a distance X. Then ...

    Text Solution

    |

  19. Two positively charged particles X and Y are initially far away from ...

    Text Solution

    |

  20. Tow particles X and Y, of equal mass and with unequal positive charge...

    Text Solution

    |