Free Vectors and Equilibrium MCQs with Answers

431 Vectors and Equilibrium MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

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.

Last updated

Read the Vectors and Equilibrium notesFree MDCAT chapter notes with key terms

431 questions · page 5 of 22

  • A. 10N
  • B. 1.366N
  • C. 13.66N
  • D. 136.6N

Explanation: To find the x-component of the resultant force when two forces of 10N magnitude are inclined at 30° and 60° with the x-axis, we need to…

Correct answer: 13.66N
  • A. 0
  • B. 1/√2 (i - j)
  • C. 1/√2 (i + j)
  • D. (i - j)/2

Explanation: Let A= (i + j) and B=(i - j). The unit vector of A = i + j / |(i + j)||(i + j)|= √12+12=2 so, the unit vector of (i + j) = i + j /√2 =…

Correct answer: 0
  • A. 23
  • B. -23
  • C. 0
  • D. 19

Explanation: To find the dot product (scalar product) of vectors A and B, you multiply the corresponding components and add them together:A · B = Ax_Bx…

Correct answer: 23
  • A. 0 ... 1
  • B. 1 ... 0
  • C. 0 ... 0
  • D. 1 ... 1

Explanation: The dot product of two vectors A and B is given by A.B = |A||B| cosθ. If the angle θ between the vectors is 0°, cosθ = 1, so a vector…

Correct answer: 1 ... 0
  • A. 7/3
  • B. 16/3
  • C. 3/7
  • D. 9/7
  • E. 5/9

Explanation: Vector Y is in 4th xy quadrantY = √(4^2 + 6^2 + 12^2)Y = √(16 + 36 + 144)Y = √196Y = 14 (Y.Z)/Y = ( 4*2 + 6*4 + 12*4)/14 = 80/14 = 5.7 =…

Correct answer: 16/3
  • A. 11.77
  • B. 22.99
  • C. 55.77
  • D. 77.81
  • E. 99.18

Explanation: S.R = lSl lRl cos (theta) 13.5=(4)(6) cos (theta) Cos -1 (13.5/24) =theta Theta= 55.77 So, option C is correct.

Correct answer: 55.77
  • A. A scalar is multiplied by a scalar
  • B. A scalar is multiplied by vector
  • C. Two vectors are multiplied to give a scalar
  • D. Sum of two scalars is taken

Explanation: The correct answer is Option C:Two vectors are multiplied to give a scalar.

Correct answer: Two vectors are multiplied to give a scalar
  • A. zero
  • B. AB
  • C. -AB
  • D. A/b
  • E. none

Explanation: The dot product of two vectors A and B is given by the formula A·B = |A| |B| cos(θ), where θ is the angle between the vectors.

Correct answer: AB
  • A. 0
  • B. 45
  • C. 60
  • D. 90

Explanation: Dot product of two vectors is obtained by multiplying their magnitudes and the cos of angle between them.

Correct answer: 90
  • A. A B sin θ
  • B. AB
  • C. AB cos θ
  • D. AB sec θ

Explanation: The scalar product, also known as the dot product, of two vectors A and B is calculated as |A||B| cos θ, where θ is the angle between the…

Correct answer: AB cos θ
  • A. Either of two vectors is a null vector
  • B. Both of the vectors are null vectors
  • C. The vectors are mutually perpendicular
  • D. All of the above

Explanation: The correct option is (d) - if A.B = 0, we can conclude that all of the options are true.

Correct answer: All of the above
  • A. A cos θ
  • B. |B|/|A|
  • C. |B|/θ
  • D. |B|cosθ

Explanation: The projection of vector B onto vector A is calculated using the formula |B|cosθ, where θ is the angle between the two vectors.

Correct answer: |B|cosθ
  • A. Not equal to the product of magnitudes of
  • B. In the plane parallel to
  • C. Perpendicular to the plane containing
  • D. Less in magnitude than the product of magnitudes of

Explanation: The vector product, or cross product, of two vectors A and B results in a vector perpendicular to the plane containing A and B.

Correct answer: Perpendicular to the plane containing
  • A. 2i + 3j + 4k
  • B. i+5j + 2k
  • C. -142+7k
  • D. 2i+5j+4k

Explanation: IT is incorrect as it shows the vector A. It represents the vector b {i+5j+2k}

Correct answer: i+5j + 2k
  • A. Unity
  • B. Zero
  • C. 90°
  • D. Depends on the vector

Explanation: The vector product, or cross product, of a vector with itself is always zero.

Correct answer: Zero
  • A. Parallel
  • B. Perpendicular
  • C. Y-axis
  • D. X- axis

Explanation: The vector product of two vectors is a vector perpendicular to both of them.

Correct answer: Perpendicular
  • A. They are parallel vectors
  • B. They are anti-parallel vectors
  • C. They are perpendicular vectors
  • D. They are rotated through 270°

Explanation: The cross-product of two vectors, A and B, is defined as a vector that is perpendicular to both A and B, with a magnitude given by…

Correct answer: They are rotated through 270°
  • A. A
  • B. 1
  • C. 2A
  • D. Zero

Explanation: The cross product of vector A with itself, denoted as A x A, is equal to zero.

Correct answer: Zero
  • A. Linear momentum
  • B. Angular momentum
  • C. Force
  • D. Electric flux

Explanation: Angular momentum is an example of a vector product of two vectors. The vector product, also known as cross product, is an operation…

Correct answer: Angular momentum
  • A. √(12/7) (2i + 3j - k)
  • B. √(7/12) (4i + 2j - 2k)
  • C. √(7/12) (2i + 3j + k)
  • D. √(3/5) (i + 2j - 3k)
  • E. √(5/12) (3i + 5j - 2k)

Explanation: The magnitude of B is equal to √(4)² + (2)² + (2)²=√24The magnitude of A is equal to √(2)² + (3)² + (1)² =√14The parallel vector is…

Correct answer: √(12/7) (2i + 3j - k)