Vectors, Physics

The resultant of two forces 3P and 2P is R. If the first force is doubled then the resultant is also doubled. then the angle between the two forces us. plz xplain with the solution?
Ans)
r2=9p2+4p2+2.6p2cosθ....................1

4r2=(6p)2+4p2+2.12cosθ..................2

dividing 2 from 1

4=(36+4+24cosθ)/(9+4+12cosθ)

9+4+12cosθ=10+6cosθ

6cosθ=-3

cosθ=-0.5

θ=120degree

Posted Date: 3/9/2013 5:21:07 AM | Location : United States





case 1, R2=(3P)2+(2P)2+2*3*2*P2*cosΘ = 9P2+4P2+12P2cosΘ = 13P2+12P2cosΘ ----->(1)

case 2, (2R)2=(6P)2+(2P)2+2*6*2*P2*cosΘ ; 4R2=36P2+4P2+24P2cosΘ = 40P2+24P2cosΘ ------->(2)

Multiply (1) by 4; 4R2=52P2+48P2cosΘ ------>(3)

(3)-(2) gives, 0=12P2+24P2cosΘ

Therefore, cosΘ = (-1/2) => Θ = cos-1(-1/2) = 120°

Posted by | Posted Date: 3/9/2013 5:23:12 AM


Related Discussions:- Vectors, Assignment Help, Ask Question on Vectors, Get Answer, Expert's Help, Vectors Discussions

Write discussion on Vectors
Your posts are moderated
Related Questions
Example 1 - A bird feeder in your yard has a total mass of 3.0 kilograms and is supported as shown. What is the force on the top wire? The bird feeder is not falling so the forc

Explain the Vector Addition of Velocity Of course the velocity is relative to how you indicate the position d. If you are moving in water that is itself moving, then your full

What is Centrifugal Force? Centrifugal force is the force that is equivalent in magnitude but opposite in direction to the centripetal force, which is the force directed toward


Q What is electromagnetic induction? The phenomenon of producing an induced emf because of the changes in the magnetic flux associated with a closed circuit is known as electr

B-Infrared (IR)  Radiant Heat Heat radiation can be achieved by using infrared (IR) radiation it penetrates about 3mm in the skin. excessive exposure can cause erythema(redden

i need a project report on logic gates urgently


explanation on polymers tga curves

The density of neutrons is of the order: (1)10 3 kg/ cc  (2)10 6 kg/cc  (3)10 9 kg/cc (4) 10 11 kg/cc Ans:(4) 10 11 kg/cc