Find the angle between two vectors  having the same length (ma

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsShort Answer Type

151. straight a with rightwards arrow on top space and space straight b with rightwards arrow on top are two vectors such that open vertical bar straight a with rightwards arrow on top close vertical bar space equals 2 comma space space space open vertical bar straight b with rightwards arrow on top close vertical bar space equals space 3 space and space straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space 3 comma find the angle between straight a with rightwards arrow on top space and space straight b with rightwards arrow on top.
83 Views

Advertisement

152.

Find the angle between two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top having the same length (magnitude) square root of 2 and their scalar products is -1.


Let straight theta be angle between straight a with rightwards arrow on top space and space straight b with rightwards arrow on top.
Now,             straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space minus 1
rightwards double arrow space space open vertical bar straight a with rightwards arrow on top close vertical bar space open vertical bar straight b with rightwards arrow on top close vertical bar space cos space straight theta space equals space minus 1 space space space space space space rightwards double arrow space space space left parenthesis square root of 2 right parenthesis thin space left parenthesis square root of 2 right parenthesis space cos space straight theta space equals space minus 1 space space space open square brackets because space open vertical bar straight a with rightwards arrow on top close vertical bar space equals space open vertical bar straight b with rightwards arrow on top close vertical bar space equals square root of 2 close square brackets
rightwards double arrow space space 2 space cos space straight theta space equals space minus 1 space space rightwards double arrow space space cos space straight theta space equals space minus 1 half space space rightwards double arrow space space space straight theta space equals space 120 degree space space space space space space space space open square brackets because space 0 space less or equal than space straight theta space less or equal than space 180 degree close square brackets

74 Views

Advertisement
153.

Find the angle between two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top such that open vertical bar straight a with rightwards arrow on top close vertical bar space equals space open vertical bar straight b with rightwards arrow on top close vertical bar space equals space 3 and straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space 1.

78 Views

154. Find the magnitude of two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top having the same magnitude and such that the angle between them is 30° and their scalar product is 3.
82 Views

Advertisement
155. Find the magnitude of two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top having the same magnitude and such that the angle between then is 60° and their scalar product is 1/2.
85 Views

156.

Find open vertical bar straight a with rightwards arrow on top close vertical bar and open vertical bar straight b with rightwards arrow on top close vertical bar comma if  open parentheses straight a with rightwards arrow on top space plus space straight b with rightwards arrow on top close parentheses. space left parenthesis straight a with rightwards arrow on top space minus straight b with rightwards arrow on top right parenthesis space equals space 12 space and space open vertical bar straight a with rightwards arrow on top close vertical bar space equals 2 space open vertical bar straight b with rightwards arrow on top close vertical bar.

72 Views

157.

Find open vertical bar straight a with rightwards arrow on top close vertical bar space and space space open vertical bar straight b with rightwards arrow on top close vertical bar space if space left parenthesis straight a with rightwards arrow on top plus straight b with rightwards arrow on top right parenthesis. space left parenthesis straight a with rightwards arrow on top space minus space straight b with rightwards arrow on top right parenthesis space equals space 8 space space and space open vertical bar straight a with rightwards arrow on top close vertical bar space equals space 8 space open vertical bar straight b with rightwards arrow on top close vertical bar.

80 Views

158.

Find open vertical bar straight a with rightwards arrow on top close vertical bar space and space open vertical bar straight b with rightwards arrow on top close vertical bar space if space space left parenthesis straight a with rightwards arrow on top plus straight b with rightwards arrow on top right parenthesis. thin space left parenthesis straight a with rightwards arrow on top minus straight b with rightwards arrow on top right parenthesis space equals 3 space and space 2 space open vertical bar straight b with rightwards arrow on top close vertical bar space equals open vertical bar straight a with rightwards arrow on top close vertical bar.

72 Views

Advertisement
159.

If left parenthesis straight a with rightwards arrow on top plus straight b with rightwards arrow on top right parenthesis. space left parenthesis straight a with rightwards arrow on top minus straight b with rightwards arrow on top right parenthesis space equals 0 show that open vertical bar straight a with rightwards arrow on top close vertical bar space equals open vertical bar straight b with rightwards arrow on top close vertical bar

74 Views

160.

If straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space straight a with rightwards arrow on top. space straight c with rightwards arrow on top comma spaceprove that either straight a with rightwards arrow on top space equals space 0 with rightwards arrow on top or straight b with rightwards arrow on top space equals space straight c with rightwards arrow on top  or  straight a with rightwards arrow on top  is perpendicular to straight b with rightwards arrow on top minus straight c with rightwards arrow on top.

89 Views

Advertisement