Question

a particle of mass 0.2kg is moving with linear velocity i-j+2k if the radius vector r=4i+j-k the magnitude of angular momentum of the particle​

Answer 1

a particle of mass 0.2kg is moving with linear velocity i-j+2k if the radius vector r=4i+j-k the magnitude of angular momentum of the particle...

solution : mass of the particle, m = 0.2kg

linear velocity of the particle, v = (i - j + 2k)

radius vector , r = (4i + j - k)

we know, angular momentum, $\vec{L}=m(\vec{r}\times\vec{v})$

= 0.2 [(4i + j - k) × (i - j + 2k) ]

= 0.2 [ 4i × (i - j + 2k) + j × (i - j + 2k) - k × (i - j + 2k) ]

= 0.2 [ (4i × i - 4i × j + 4i × 2k) + (j × i - j × j + j × 2k) - (k × i - k × j + k × 2k)]

= 0.2 [ (0 - 4k - 8j) + (-k - 0 + 2i) - (j + i + 0)]

= 0.2 [ i -9 j - 5k ]

= (i - 9j - 5k)/5

hence, angular momentum of the particle is (i - 9j - 5k)/5

Answer 2

Answer:

$\sqrt{4.28} \: units$