o level physic problem

• pandemona

  15 Oct 07, 00:53

  Two bodies P and Q on a smooth table are of masses 2kg and 3kg respectively. They are connected by an inelastic string and Q is pulled by a force of 15N. Find the tension T in the string
• airgrinder

  15 Oct 07, 01:00

  5N?
  
  Error: Message must be at least 8 characters long.
• eagle

  15 Oct 07, 01:03

  Originally posted by pandemona:

  Two bodies P and Q on a smooth table are of masses 2kg and 3kg respectively. They are connected by an inelastic string and Q is pulled by a force of 15N. Find the tension T in the string

  F=ma for both
  and a is the same for both
  
  so total force required = 2(a) + 3(a) = 15N
  a = 3N
  
  As tension T is used to pull P,
  T = 2a = 6N
• Deadly

  15 Oct 07, 01:11

  Originally posted by eagle:
  F=ma for both
  and a is the same for both
  
  so total force required = 2(a) + 3(a) = 15N
  a = 3N
  
  As tension T is used to pull P,
  T = 2a = 6N[/b]

  not quite sure if acceleration is measured in newtons...
• ^tamago^

  15 Oct 07, 01:15

  the idea is there. though if u wan to dimensionally right then be it.
• eagle

  15 Oct 07, 01:18

  paiseh
  
  me do mentally and at a very tired state now
• airgrinder

  15 Oct 07, 01:20

  Originally posted by Deadly:

  not quite sure if acceleration is measured in newtons...

  consider the whole diagram
  
  total mass = 5kg.
  total force applied is 15N
  hence a = 3m/s2
• absol

  16 Oct 07, 16:44

  Originally posted by pandemona:

  Two bodies P and Q on a smooth table are of masses 2kg and 3kg respectively. They are connected by an inelastic string and Q is pulled by a force of 15N. Find the tension T in the string

  lemme try...er since they mus have same accel, accel of Q is 5m/s^2...so P mus also go at 5m/s^2...
  hence force pulling P is 5*2 = 10N
  tension T = total force = 10+15=25N...correct or wrong?
• ^tamago^

  16 Oct 07, 16:46

  Originally posted by absol:

  lemme try...er since they mus have same accel, accel of Q is 5m/s^2...so P mus also go at 5m/s^2...
  hence force pulling P is 5*2 = 10N
  tension T = total force = 10+15=25N...correct or wrong?

  how u get 5m/s² in the first place?
• lpx88

  16 Oct 07, 16:50

  Originally posted by ^tamago^:

  how u get 5m/s² in the first place?

  X2
• absol

  16 Oct 07, 17:29

  f=ma, q's mass is 3kg, its being pulled by 15N 15/3 = 5m/s^2?
• angelfairy

  16 Oct 07, 17:32

  Originally posted by absol:

  f=ma, q's mass is 3kg, its being pulled by 15N 15/3 = 5m/s^2?

  doesnt work that way, consider the system as a whole
• absol

  16 Oct 07, 17:50

  "Find the tension T in the string"
  
  nvm. take it as qns fault since qns nv specify which part of the string tension is T
• pandemona

  16 Oct 07, 18:01

  Originally posted by absol:

  "Find the tension T in the string"
  
  nvm. take it as qns fault since qns nv specify which part of the string tension is T

  they are connected by an inelastic string
• ^tamago^

  16 Oct 07, 18:03

  Originally posted by absol:

  "Find the tension T in the string"
  
  nvm. take it as qns fault since qns nv specify which part of the string tension is T