Thursday

March 5, 2015

March 5, 2015

Posted by **Wykeena** on Sunday, June 12, 2011 at 7:49pm.

Find the angle between the two vectors. Hint: Find the angle each makes with the +x-axis.

- physics -
**bobpursley**, Sunday, June 12, 2011 at 8:19pmdo the dot product, and the magnitude of the cross product.

cross product= r1XR2=magR1*magR2*sinTheta

dot product= magR1*magR2*cosTheta

cross product/dot product = tan theta

solve for theta.

How do you get cross product?

r1XR1=(2.3i-4.74j)X(3.02i+.85j)

= 2.31iX(3.02i+.85j) + (-4.74j)X(3.02i+.85j)

well iXi=0, iXj= k, jXi=-k, jXj=0

or = 2.31*.85k+4.74*3.02k=CCCCc

How do you get the dot product?

r1.r2= 2.3*3.02-4.74*.85=DDDDD

so tan theta = CCCCC/DDDDDD

- physics -
**bobpursley**, Sunday, June 12, 2011 at 8:21pmI see I missed a sign on R2, correct that please.

**Answer this Question**

**Related Questions**

physics - The problem concern the position vectors r1=2.43mi-4.74mj and r2=-3....

physics - The problem concern the position vectors r1=2.43mi-4.74mj and r2=-3....

Trig - I need help with my vectors unit. I'm really confused about how to set ...

science (physics) Need to solve this today please - (a) Express the vectors A, B...

Physics - Find the scalar product of the vectors ai+bj and bi-aj . Where a and b...

physics - The three displacement vectors in the drawing have magnitudes of A = 5...

Pre Cal/Vectors - Can someone show the steps involved in figuring out this type ...

Vectors (Physics/Math) - Vector A has a magnitude of 18 (in some unspecified ...

Calculus - For which following condition, will the dot product of two vectors be...

math - if vectors a+b+c=0 and modulus of the vectors a, b and c are 3 ,5 and 7 ...