Answer:
a) 0°
b) 180°
c) 90°
Explanation:
Hello!
To solve this question let <em>a </em> be the vector whose length is 15 m and <em>b</em> the vector of length 20 m
So:
|<em>a </em>| = 15
|<em>b </em>| = 20
Since we are looking for the angle between the vectors we need to calculate the length of the sum of the two vectors, this is:
Now we replace the value of the lengths:
--- (1)
Now, if:
a) |a+b| = 35
First we can see that 20 + 15 = 35, so the angle must be 0, lets check this:
and :
θ = 0
b) |a+b|=5
From eq 1 we got:
--- (2)
θ = π or θ = 180°
c) |a+b|=25
θ = π/2 or θ = 90°