The scalar product of (2i - j + 3k).(3i + 2j - k)?
Correct answer: A. 1
- A. 1
- B. 2
- C. 10
- D. 20
- E. 25
Explanation
The scalar product (also known as the dot product) of two vectors is calculated by multiplying their corresponding components and adding the results: (2i-j+3k) • (3i+2j-k) = 2×3 + (-1)×2 + 3×(-1) = 6 - 2 - 3 = 1. Options B, C, D, and E are incorrect as they result from miscalculations in either the component multiplication or the addition of these products.
Last updated
About Vectors and Equilibrium
Vectors have magnitude and direction, unlike scalars, and are combined by head-to-tail or parallelogram methods. Work covers rectangular components, equilibrium when the resultant force is zero, the scalar product for work and projections, and the vector product for torque and cross-product direction using the right-hand rule.
Practise Vectors and Equilibrium
431 free Vectors and Equilibrium MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 15 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A.B = B.A =_.
A body will be in translational equilibrium if the vector sum of all the forces acting on it is:
A constant force F= 2i + 3j +4k is applied on a body. What will be the work done to move the body 5m in the z-direction?
A force F of magnitude 20N is acting on an object making an angle of 30° with the X-axis. Its Fy component is
A force of 10N is acting along y-axis. Its component along x-axis is