Mastering Cross and Dot Products for Test Review

Thread starter 1man
Start date Apr 21, 2010
Tags

Cross Cross product Dot Dot product Product

AI Thread Summary

To calculate the cross product of (2A)x(3B), first determine the individual vectors A and B, then apply the scalar multiplication before using the standard cross product formula. For finding the angle theta between two vectors given their components, use the dot product formula and the magnitudes of the vectors. The dot product of 2A and 3B is calculated as 2A · 3B, which can be simplified to 6(A · B). The vectors (2A) and (3B) are normal vectors, confirming that the cross product can be computed. Understanding these concepts is essential for mastering vector operations in preparation for the test.

Apr 21, 2010

1man

i'm reviewing for a test and I can't remember how to do the cross product of (2A)x(3B)
or how to find the angle theta when given components. or dot product: 2A . 3B

Physics news on Phys.org

Apr 21, 2010

willem2

Are (2A) and (3B) normal vectors? If so, the link in your own post will tell you
how to do a cross product. If not, what are they?

Apr 21, 2010

1man

they are and i already know
Rz=Az+Bz
Ry=Ay+By
Rz=Az+Bz

but I am not sure how to do (2A)x(3C)

Apr 21, 2010

1man

or (2A)x(3B)

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...

View full post »

Thread 'Explain this asphalt sheen'

This problem is two parts. The first is to determine what effects are being provided by each of the elements - 1) the window panes; 2) the asphalt surface. My answer to that is The second part of the problem is exactly why you get this affect. And one more spoiler:

View full post »

Thread 'A cylinder connected to a hanged mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...

View full post »