Answer:
magnitude = 3
unit vector = 
Explanation:
Given vectors:
u = 2i + 2j - k
v = -i + k = -i + 0j + k
(a) u x v is the cross product of u and v, and is given by;
![u X v = \left[\begin{array}{ccc}i&j&k\\2&2&-1\\-1&0&1\end{array}\right]](https://tex.z-dn.net/?f=u%20X%20v%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Di%26j%26k%5C%5C2%262%26-1%5C%5C-1%260%261%5Cend%7Barray%7D%5Cright%5D)
u x v = i(2+0) - j(2 - 1) + k(0 - 2)
u x v = 2i - j - 2k
Now the magnitude of u x v is calculated as follows:
| u x v | = 
| u x v | = 
| u x v | = 
| u x v | = 3
Therefore, the magnitude of u x v is 3
(b) The unit vector û parallel to u x v in the direction of u x v is given by the ratio of u x v and the magnitude of u x v. i.e
û = 
u x v = 2i - j - 2k [<em>calculated in (a) above</em>]
|u x v| = 3 [<em>calculated in (a) above</em>]
∴ û = 
∴ û =
Control rods<span> are </span>rods<span>, plates, or tubes containing a neutron absorbing material (material with high absorbtion cross-section for thermal neutron) such as boron, hafnium, cadmium, etc., used to </span>control<span> the power of a nuclear reactor.
so the statement that describe a control rod is:
</span><span>Control rods are lowered into the reactor to slow down the reaction by absorbing neutrons.</span>
Answer:
the mass is distributed uniformly in an atom
It’s red shift and blue shift because This only occurs when the frequency of the wave is made longer or shorter due to the movement of the source relative to the observer
