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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(hat(i)-2hat(j)+3hat(k))`

B

`5(4hat(i)+2hat(j)+3hat(k))`

C

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

D

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

Text Solution

Verified by Experts

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