JEE Physics - Scalars and Vectors

Buy JEE Main Engineering Entrance Exam (Pro) Practice test pack

Question - 1

If a unit vector is represented as \((0.8 \hat{\mathrm{i}}+b \hat{\mathrm{j}}+\sqrt{0.2} \hat{\mathrm{k}})\) then the value of 'b' must be ___________

  • A 2.3
  • B 5.2
  • C 1.2
  • D 0.4

Question - 2

For a regular hexagon ABCDEF with O as its centre.

\(\text { If } \overrightarrow{\mathrm{AB}}+\overrightarrow{\mathrm{AC}}+\overrightarrow{\mathrm{AD}}+\overrightarrow{\mathrm{AE}}+\overrightarrow{\mathrm{AF}}=\mathrm{n} \overrightarrow{\mathrm{AO}}\) then the value of 'n' is _____________.

  • A 10
  • B 12
  • C 5
  • D 6

Question - 3

The magnitude of sum of two vectors is equal to the magnitude of difference of the two vectors. The angle (in degrees) between these vectors is __________.

  • A 14
  • B 52
  • C 90
  • D 32

Question - 4

The vectors \(\overrightarrow{\mathrm{A}}, \ \overrightarrow{\mathrm{B}} \ \text { and } \ \overrightarrow{\mathrm{C}}\) are such that \(|\vec{A}|=|\vec{B}|,|\vec{C}|=\sqrt{2}|\vec{A}| \ \text { and } \ \vec{A}+\vec{B}+\vec{C}=0\). The angle (in degrees) between \(\vec{B} \text { and } \vec{C} \text { is }\)______________.

  • A 452
  • B 120
  • C 135
  • D 25

Question - 5

If a vector \(2 \hat{\mathrm{i}}+3 \hat{\mathrm{j}}+2 \hat{\mathrm{k}}\) is perpendicular to the vector \(-3 \hat{\mathrm{i}}+8 \hat{\mathrm{j}}+\alpha \hat{\mathrm{k}}\)  then the value of \(\alpha\) is _____________

  • A 12
  • B -94
  • C -9
  • D 12

Question - 6

The linear velocity of a rotating body is given by \(\overrightarrow{\mathrm{V}}=\vec{\omega} \times \overrightarrow{\mathrm{r}}\),\(\text { where } \vec{\omega}\), is the angular velocity and \(\overrightarrow{\mathrm{r}}\)is the radius vector. The angular velocity of a body is \(\vec{\omega}=\hat{\mathrm{i}}-2 \hat{\mathrm{j}}\) and the radius vector \(\overrightarrow{\mathrm{r}}=2 \hat{\mathrm{j}}-3 \hat{\mathrm{k}}\) then \(|\vec{v}|\) is ______________units.

  • A 8
  • B 5
  • C 7
  • D 1

Question - 7

The moment of the force, \(\overrightarrow{\mathrm{F}}=4 \hat{\mathrm{i}}+5 \hat{\mathrm{j}}-6 \hat{\mathrm{k}}\) at (2, 0, -3) about the point (2, -2, -2), is given by \(a \hat{i}+b \hat{j}+c \hat{k}\) . Find the value of 'c'.

  • A -8
  • B 45
  • C 4
  • D 6

Question - 8

If resultant of two vectors having magnitudes 4 and 5 is l, then the value of their cross product will be___________.

  • A 14
  • B 5
  • C 2
  • D 0

Question - 9

Scalar product of two vectors is \(2 \sqrt{3}\) and the magnitude of their vector product is equal to 2, then the angle (in degrees) between them will be _____________.

  • A 30
  • B 22
  • C 21
  • D 45

Question - 10

The magnitude of displacement vector with end points ( I l, - 5) and (- 10. 1 5 ) must be __________units.

  • A 30
  • B 12
  • C 29
  • D 23
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next
Previous Next