Chapter 2 Vectors and equilibrium.


1. θ is the angle made with +X direction in  Anticlockwise Sense

2. Two vectors of same magnitude result vector of same magnitude  by  Angle of 1200

3. If both Rx and Ry are positive the θ lies in  I Quadrant 

4. If Rx is positive and Ry is negative the θ lies in II Quadrant

5. If both Rx and Ry are negative the θ lies in III Quadrant

6. If Rx is negative and Ry is positive the θ lies in IV Quadrant

7. A . B = AB Cosθ

8. A x B = AB Sinθ

9. Scalar product (work and power) is also called Dot product

10. Vector product (torque) is also called Cross product

11. ABCosθ, here A is magnitude of 1st vector while B is that component of B which is Parallel to A

12. ABSinθ, here A is magnitude of 1st vector while B is that component of B which is Perpendicular to A

13. The point of rotation in torque is called Fulcrum or Pivot

14. Torque is rotational analogue of Force

15. For concurrent forces, the line of action of  are  Common

16. If 1st condition is satisfied the body will be in translational equilibrium and there will be no Linear acceleration

17. If 2nd  condition is satisfied the body will be in translational equilibrium and there will be no Rotational Acceleration

18. If both condition are satisfied the body has  Zero acceleration

19. Difference of two vectors divided by scalar must also be Vector

20. Deceleration is also called Retardation

21. If x-component of vector is 3x and y-component is -3y the angle of its resultant is 3150

22. Mass  Scalar

23. Acceleration,  momentum, electric intensity Vector

24. The magnitude of resultant of two forces is 2F. if the magnitude of each force is F than the angle between these forces is  00

25. Three vectors of equal magnitude are acting on three sides of an equilateral triangle .the magnitude of their resultant is zero

26. Two concurrent forces have maximum resultant of 45N and minimum of 5N These are 20N and 25N

27. Two vectors are such that a+b =b+a the angle between them is 900

28. A unit vector is obtained by dividing the vector with its magnitude  not the direction

29. Impulse is  Vector quantity

30. When vector is multiplied by negative number its direction  Change by 1800

31. The resultant of two forces, each of magnitude 5N has resultant of 5N, the angle between the forces are  1200

32. In the self cross product, the angle is  Zero degree

33. Two equal forces make an angle 1800 with each other. The magnitude of their resultant is  Zero

34. the scalar product of two vectors A and B making an angle θ with each other is given by  lAl lBl cosθ

35. The scalar product of two vector is zero, when they are  Perpendicular to each other

36. If two vectors are parallel to each other, their resultant is  Zero

37. 5N is  Vector quantity 

38. Area of parallelogram in which the two adjacent sides are A and B is given by  Absinθ

39. The vector product is also called  Cross product