Recall the definition of the cross product with respect to the unit vectors:
i × i = j × j = k × k = 0
i × j = k
j × k = i
k × i = j
and that the product is anticommutative, so that for any two vectors u and v, we have u × v = - (v × u). (This essentially takes care of part (b).)
Now, given a = 8i + j - 2k and b = 5i - 3j + k, we have
a × b = (8i + j - 2k) × (5i - 3j + k)
a × b = 40 (i × i) + 5 (j × i) - 10 (k × i)
… … … … - 24 (i × j) - 3 (j × j) + 6 (k × j)
… … … … + 8 (i × k) + (j × k) - 2 (k × k)
a × b = - 5 (i × j) - 10 (k × i) - 24 (i × j) - 6 (j × k) - 8 (k × i) + (j × k)
a × b = - 5k - 10j - 24k - 6i - 8j + i
a × b = -5i - 18j - 29k
Answer:
true
Explanation:
as long as you are interested, you are happy
Answer:
Natural selection is a mechanism, or cause, of evolution.
Explanation:
Adaptations are physical or behavioral traits that make an organism better suited to its environment. Heritable variation comes from random mutations.
Answer:
A, the energy an object has due to its motion.
Explanation:
Kinetic energy is the energy created by motion.
Answer:
1200 W
Explanation:
Power is given by the ratio between work done and time taken:
where W is the work done and t the time taken.
In this problem, W = 3600 J and t = 3.0 s. Therefore, the power in this exercise is
