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The position vectors of two balls are gi...

The position vectors of two balls are given by
`vec(r )_(1)=2 (m)i+7(m)j`
`vec(r )_(2)= -2(m)i+4(m)j`
What will be the distance between the two balls?

A

`4m`

B

`4.5 m`

C

`5 m`

D

`3 m`

Text Solution

Verified by Experts

The correct Answer is:
C
`vec(r )_(1)= 2(m)hat(i)+7(m)hat(j)`
`vec(r )_(2)= -2mhat(i)+4 mhat(j)`
`:. vec(r )_(1)-vec(r )_(2)= [2-(-2)]hat(i)+(7-4)hat(j)`
`:. |vec(r )_(1)-vec(r )_(2)|= sqrt((4)^(2)+(3)^(2))= sqrt((5)^(2))= 5 m`
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