# Determine the magnitude of the minimum acceleration

• tristanmagnum
In summary, a 76-kg petty thief needs to find the minimum acceleration that the sheets tied together can support in order to escape from a third-story jail window. The makeshift rope can only support a mass of 58 kg. The equation T-mg=ma can be used, with tension as the upward force and mg (weight) as the downward force. The signs of the forces will depend on how the positive direction is defined, with a negative result expected if acceleration is defined upward. The mass of the sheets is not relevant, as it is the weight they can withstand that matters.

## Homework Statement

A 76-kg petty thief wants to escape from a third-story jail window. Unfortunately, a makeshift rope made of sheets tied together can support a mass of only 58 kg.Determine the magnitude of the minimum acceleration at which the thief can descend using the rope.

i think T-mg=ma?

## The Attempt at a Solution

i know tension would be the upward force and mg (weight) would be the upward force correct?

The signs are going to depend on how you define the positive direction. Your equation is fine if the aceleration a is defined upward (so expect a negative result).

haruspex said:
The signs are going to depend on how you define the positive direction. Your equation is fine if the aceleration a is defined upward (so expect a negative result).

would i use the mass of the man or the mass that the sheet can with stand?

tristanmagnum said:
would i use the mass of the man or the mass that the sheet can with stand?
The question is not quite right. It should say that the sheets can withstand a weight of 58g N. Mass is not force.

What would the tension be if a man of 58 kg chose to rest from it?