Answer:
The magnitude of the given vector is 40.72 units.
Step-by-step explanation:
The given vector is [tex]v=-3\widehat{i}+40\widehat{j}+7\widehat{k}[/tex]
We know that for any vector 'r' [tex]\overrightarrow{r}=x\widehat{i}+y\widehat{j}+z\widehat{k}[/tex] the magnitude is given by
[tex]|r|=\sqrt{x^{2}+y^{2}+z^{2}}[/tex]
Comparing with the given vector we have
x = -3
y = 40
z = 7
Thus the magnitude equals
[tex]|v|=\sqrt{(-3)^{2}+40^{2}+7^{2}}[/tex]
[tex]|v|=40.72[/tex]