Advertisements
Advertisements
प्रश्न
Read the statement below carefully and state with reason, if it is true or false:
Three vectors not lying in a plane can never add up to give a null vector.
विकल्प
True
False
उत्तर
This statement is True.
Explanation:
Three vectors, which do not lie in a plane, cannot be represented by the sides of a triangle taken in the same order.
APPEARS IN
संबंधित प्रश्न
State with reasons, whether the following algebraic operations with scalar and vector physical quantities are meaningful:
- adding any two scalars,
- adding a scalar to a vector of the same dimensions,
- multiplying any vector by any scalar,
- multiplying any two scalars,
- adding any two vectors,
- adding a component of a vector to the same vector.
Read the statement below carefully and state with reason, if it is true or false:
The magnitude of a vector is always a scalar.
Read the statement below carefully and state with reason, if it is true or false:
The average speed of a particle (defined as total path length divided by the time taken to cover the path) is either greater or equal to the magnitude of average velocity of the particle over the same interval of time.
The position of a particle is given by
`r = 3.0t hati − 2.0t 2 hatj + 4.0 hatk m`
Where t is in seconds and the coefficients have the proper units for r to be in metres.
- Find the v and a of the particle?
- What is the magnitude and direction of velocity of the particle at t = 2.0 s?
Read the statement below carefully and state, with reason and example, if it is true or false:
A scalar quantity is one that must be dimensionless.
Read the statement below carefully and state, with reason and example, if it is true or false:
A scalar quantity is one that does not vary from one point to another in space.
The angle between A = `hati` + `hatj` and B = `hati` − `hatj` is ______.
If |A| = 2 and |B| = 4, then match the relations in column I with the angle θ between A and B in column II.
| Column I | Column II |
| (a) A.B = 0 | (i) θ = 0 |
| (b) A.B = + 8 | (ii) θ = 90° |
| (c) A.B = 4 | (iii) θ = 180° |
| (d) A.B = – 8 | (iv) θ = 60° |
If the projection of `2hat"i"+4hat"j"-2hat"k"` on `hat"i"+ 2hat"j"+alphahat"k"` is zero. Then, the value of α will be ______.
A force `vec"F"=(hat"i"+2hat"j"+3hat"k")`N acts at a point `(4hat"i"+3hat"j"-hat"k")`m. Then the magnitude of torque about the point `(hat"i" + 2hat"j" + hat"k")` m will be `sqrtx` N-m. The value of x is ______.
