Concepts Of Physics MCQ Edition [Volume 1]
- Exam
- Concepts Of Physics MCQ Edition [Volume 1]
- Subject
- Physics
- Chapter
- Physics and Mathematics
Concepts Of Physics MCQ Edition [Volume 1] · Physics · Physics and Mathematics
For the resultant of several vectors, its x-component
For the resultant of several vectors, its x-component
Options
- Aequals the sum of the x-components of the individual vectors
- Bmight be equal to the sum of the magnitudes of the vectors
- Cmight be less than the sum of the magnitudes of the vectors
- Dmight be greater than the sum of the magnitudes of the vectors
Correct answer
C. might be less than the sum of the magnitudes of the vectors
Step-by-step solution
Let the vectors be .
The resultant vector is .
Taking the x-component on both sides, . Thus, the x-component of the resultant equals the sum of the x-components of the individual vectors.
The magnitude of the resultant satisfies .
Since the x-component of any vector cannot exceed its magnitude, .
Combining these inequalities gives .
If all vectors are directed along the positive x-axis, .
If the vectors are not all directed along the positive x-axis, .
Therefore, the x-component of the resultant might be equal to or less than the sum of the magnitudes of the vectors, but it can never be greater.
The resultant vector is .
Taking the x-component on both sides, . Thus, the x-component of the resultant equals the sum of the x-components of the individual vectors.
The magnitude of the resultant satisfies .
Since the x-component of any vector cannot exceed its magnitude, .
Combining these inequalities gives .
If all vectors are directed along the positive x-axis, .
If the vectors are not all directed along the positive x-axis, .
Therefore, the x-component of the resultant might be equal to or less than the sum of the magnitudes of the vectors, but it can never be greater.