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The position vector of 1 kg object is \( \vec{r}=(3 \hat{i}-j) m \) and its velocity \( \vec{v}=(3 \hat{\jmath}+\hat{k}) \). The magnitude of angular momentum is \( \sqrt{x} Nm \) where \( x \) is equal to

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The position vector r and the velocity vector v of the object are given as:

\(-\vec r = 3 \hat i - \hat j m\)

\(- \vec v = 3 \hat j + \hat k m/s\)

The mass m of the object is 1 kg.

The linear momentum \(\vec p\) is given by the formula:

\(\vec p = m\vec v\)

Substituting the values:

\(\vec p = 1.(3\hat j + \hat k) = 3 \hat j + \hat k\, kg\, m/s\)

The angular momentum \(\vec L\) is given by the cross product of the position vector \(\vec r\) and the linear momentum \(\vec p\):

\(\vec L= \vec r \times \vec p\)

Substituting the values:

\(\vec L = (3\hat i - \hat j) \times (3 \hat j + \hat k)\)

We can calculate the cross product using the determinant:

Calculating the determinant, we expand it as follows:

Calculating each of these determinants:

The magnitude of \(\vec L\) is given by:

We are told that the magnitude of angular momentum is √x Nm. Therefore, we have:

√x = √91

This implies:

x = 9

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