- #1

thebosonbreaker

- 32

- 5

## Homework Statement

A mass of 50 grams hangs in equilibrium on a string. The mass is pulled aside and upwards by a force of 0.3N which makes an angle of 30° with the horizontal. Find the angle that the string makes with the vertical and the tension in the string.

## Homework Equations

Body is in equilibrium, so I will need to resolve forces (tension and weight).

## The Attempt at a Solution

For the first part of the question (find the angle that the string makes with the vertical):

I do not understand why this is not 60° - the string will move in the same direction as the 0.3N force applied to it, so if it makes an angle of 30° with the horizontal (the angle between 'horizontal'/'vertical' being a right angle), the angle made with the vertical must be: 180 - (90 + 30) = 60°. Could somebody please explain why this is not the case and how to find the angle?

For the second part of the question (finding the tension in the string):

Resolving horizontally I have that: Tcos30° = 0.3 [the horizontal component of tension equals the horizontal force applied]

Resolving vertically I have that: Tsin30° = mg = 0.05g

These both lead to different answers for T.

Could somebody clraify this problem? I'm having a bit of a hard time with it.

Thanks a lot in advance, your help will be greatly appreciated!