If we refer to a plastic bag (or fabric bag) that its content went outside due to a an heavy weight which the bag can't carry. Which one is more natural?
There are a few things that could be improved in the OP's question, other than choosing which verb is preferable.
When we talk about a plastic bag that breaks due to its weight, which word is more common: rip or tear?
The OP's sample sentence
The fruits fell down on the street's ground because the bag was torn.
The sample sentence is comprehensible but unnatural sounding. Normally, fruit is uncountable. “We bought some fruit in the market”. “Eating fruit and vegetables is good for you” etc. I would say the verb break is more commonly used, e.g. “Nowadays, a plastic bag is more likely to break when it's carrying heavy stuff.” Lastly, a street comprises of the ground, there's no need to say “street's ground” just say “street” or “ground”.
The plastic bag broke/ripped and the fruit, which was inside, fell onto the ground
The plastic bag broke/ripped and the fruit fell to the street.
If someone wanted to say why the fruit was on the ground, or what happened after the bag broke, they could say
- The fruit was on the ground because the bag (holding it) broke.
- The fruit fell onto the sidewalk when the plastic carrier [bag] got broken/torn/ripped.
- The fruit was on the ground because the bag was broken/torn/ripped.
I feel that broke and ripped are only interchangeable in sentences 1 while in #2 and #3 any of the terms mentioned above could be used.