Chapter 2 Notes | Physics 1st Year

“Vectors and Equilibrium”

Index:

1. Basic Concept of vectors.
2. Vectors.
3. Rectangular Coordinate system.
4. Addition of Vectors.
5. Resultant Vectors.
6. Vectors Subtraction.
7. Multiplication of a Vector with a Scalar.
8. Unit Vector.
9. Null Vector.
10. Equal Vectors.
11. Rectangular Components of a Vector.
12. Determination of a Vector from its Rectangular Components.
13. Position Vector.
14. Vector Addition by Rectangular Components.
15. Product of two Vectors.
16. Vector or Cross Product.
17. Torque.
18. Equilibrium of Forces.
19. First Condition of Equilibrium.
20. Second Condition of Equilibrium.

See Also: 1st Year Paper Scheme 2021

See Also: 2nd Year Paper Scheme 2021

Key Points:

1. The arrangements of mutually perpendicular axes is called rectangular or  Cartesian coordinate system.
2. A scalar is a quantity that has magnitude only, whereas a vector is a quantity has both direction and magnitude.
3. The Sum Vector of two or more vectors is called resultant vector.
4. Graphically the vectors are added by drawing them to a common scale placing them head to tail, the vector connecting the tail of first to the head of the last vector is the resultant vector.
5. Unit Vectors describe directions in space. A unit vector has a magnitude of 1 with no units.
6. A vector of magnitude zero without any specific direction is called null vector
7. The vector that describes the location of a particle with respect to the origin is called position vector.
8. A body is said to be in equilibrium under the action of several forces if the body has zero transnational acceleration and angular acceleration.
9. For a body to be in transnational equilibrium the vector sum of all the forces acting on the body must be zero.
10. The torque is defined as the product of the force and the moment arm.
11. The moment arm is the perpendicular distance from the axis of rotation to the direction of line of action of the force.
12. For a body to be in rotational equilibrium,the sum of torques on the body about any axis must be equal to zero.