The magnitude of displacement (in m) covered by a particle in first two seconds if its position vector is given as `vecr = 2 t ^(2) hati + 3 t hatj + 9 hatk.`

Answer

`10.00`

Explanation

`vecr = 2 t ^(2) hati + 3 t hatj + 9 hatk`
`At t = 0, vecr _(1) = 9 hatk`
`At t = 2 s, vecr _(2) = 8 hati + 6 hatj + 9 hatk,`
`therefore Delta vecr = vecr _(2) = vecr_(1) = 8 hati + 6 hatj`
`therefore | Delta vecr| = | vecr _(2) - vecr _(1)|`
`= sqrt ((8) ^(2) + (6) ^(2)) = 10 m`