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
Production of electricity : Very large amounts of electrical energy lie dormant in the atoms of every speck of material in the universe. Whilst the atoms remain electrically ba

Explain the thermal detectors method of detection of ultrasonic waves. Thermal detectors method: It is the most generally used method of detection of ultrasonic waves. In th

A 95.7-nm film of an unknown substance is able to prevent 555-nm light from being reflected when surrounded by air. What is the index of refraction of the substance   2d


A more forceful argument which the weak principle: This implies that if the laws of the Universe were not favorable to the development of intelligent creatures to ask regarding the

Ascooter acquires velocity of 36km/hr in 10 secs just after the start and stops after 20 secs. Find the acceleration in both cases.

Electric Potential: Electric Potential verifies the flow of charge. Its unit is volt, represented as "v".

Determine the Applications of MOSFET MOSFETs can  also  be  used  for  most  applications  where JFET is used. MOSFETs have become very popular for  digital logic circuits bec

An organ pipe which is open at both ends resonates at its fundamental frequency. Neglecting any end effects, what wavelength is formed by this pipe in this mode of vibration if the

name 3 things that will change how many times your heartbeats per day..