a) What is the minimum time in which one can hoist a 1.00-kg rock height of 10.0m if the string used to pull the rock up has a breaking strength of 10.8 N? Assume the rock to be initially at rest.(adsbygoogle = window.adsbygoogle || []).push({});

b) If the string is replaced by one that is 50% stronger, by what percentage will the minimum time for the hoist be reduced.

a)

i just used a= 2(x-xo)/t^2 and then i got 2(10)/t^2 = 10.8/1

so i got 10.8=20/t^2 and so t would be root 10.8 but the answer is 4.5seconds... how?

b) i need to get a) to solve this...

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Minimum time for a tension

**Physics Forums | Science Articles, Homework Help, Discussion**