Resolving the forces for an object suspended on two strings.

Imagine a following situation: a stationary (not moving) object with a mass of 5 kg is suspended in the air by two strings. The angles between strings and the vertical directions are 15 and 55 degrees. What are tensions T1 and T2 in both strings?The first thing to do would be just drawing a simple diagram. I don't think it's possible to add one here, but I drew a little diagram myself! Now, we have to resolve the forces in the horizontal and vertical directions. Because the object is stationary, according to Newton's laws of dynamics we know that adding all the forces will equal 0. Let's start!Vertical forces: we have two vertical components of tension T1 and T2 pointing upwards (call it +ve direction) and weight i.e. 5g pointing downwards (let's take g = 9.8). So: T1cos(15o) + T2cos(55o) - 59.8 = 0  (eqn. 1)Horizontal forces: one component points to the left (-ve direction), the other to the right (+ve direction). Hence: T1sin(15o) - T2sin(55o) = 0  (eqn. 2)We can see equations 1 and 2 form a set of simultaneous equations. Let's rearrange 2 to get T1 in terms of T2: T1 = T2sin(55o) / sin(15o)  (eqn. 3).Substituting equation 3 into equation 1 gives: T2sin(55o)*cot(15o) + T2cos(55o) = 49  (eqn. 4) .From equation 4: T2 = 13.5 N and hence from equation 3: T1 = 42.7 N.

FW
Answered by Filip W. Physics tutor

18987 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

The energy of a photon is 1.5MeV. Calculate the frequency associated with this photon energy and state an appropriate unit in your answer.


Explaining how capacitors work


A ball is initially at rest and is dropped from a height of 10m. Calculate the velocity of the ball when it reaches the ground


Bismuth-208, which has an atomic mass of 208u and 83 protons in the nucleus, decays through the emission of 2 alpha particles and a beta-positive particle. What isotope results from this decay?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning