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A bird moves from point (1 m, -2 m, 3 m)...

A bird moves from point `(1 m, -2 m, 3 m)` to `(4 m, 2 m, 3 m)`. If the speed of the bird is `10 m//s`, then the velocity vector of the bird in `m//s` is:

A

`5 (hati-2hatj+3hatk)`

B

`5 (4hati+2hatj+3hatk)`

C

`0.6 hat(i)+0.8 hat(j)`

D

`6hat(i)+8hat(j)`

Text Solution

Verified by Experts

The correct Answer is:
D
`vec(v)=((4-1)hat(i)+(2+2)hat(j)+(3-3)hat(k))/sqrt(3^(2)+4^(2)+0^(2))=(3hati+4hatj)/5`
`vec(v)=|vec(v)|hat(v)=10((3hat(i)+4hatj)/5)=6hat(i)+8hat(j)`
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Knowledge Check

  • A bird flies from (-3m, 4m, -3 m) to (7m, -2m, -3m) in the xyz-coordinates. The bird's displacement vector is given by

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