Question

A particle starts from rest at the point A(1, 2, -3) m and reaches at the point B(3, 4, 5) m. The magnitude of displacement of man is

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Answer 1

Answer :-

|AB| = 8.5 m

Explaination :-

Let i, j & k be unit vectors along X - axis, Y - axis & Z - axis.

A = i + 2j - 3k

B = 3i + 4j + 5k

Displacement of the man is calculated by -

AB = B - A

AB = (3i + 4j + 5k) - ( i + 2j - 3k)

AB = 2i + 2j + 8k

Magnitude of displacement is calculated by -

|AB| = √(2² + 2² + 8²)

|AB| = √(4 + 4 + 64)

|AB| = √(72)

|AB| = 2√18

|AB| = 8.48 m

From the options, 8.5 m is the most appropriate.

Thanks ...

Answer 2

Refer to the Attachment.

Refer to the Attachment.Hope it Helps !!!!!