No, ambiguity was introduced when the measurement was switched from force to mass. The question remains: what is the weight/force experienced on the wheels on Mars? Knowing the mass won't tell us unless we also know the acceleration due to gravity on Mars.
The pound is a unit of mass, same as the kg (it's defined as exactly 0.45359237kg). Just as 900kg is 900kg everywhere, 2000lb is 2000lb everywhere. The colloquial weight is literally a force, and its imperial unit is thus the pound-force.
This is incorrect. The pound is a unit of force, similar to a Newton. The pound-mass(notated lb-m) is similar to the kg. The conversation you gave above is based on Earth gravity for weight.
There are about a dozen different units that are all called "pounds," and you have to rely on context to know which is meant. When I took physics in high school, pounds were always force (abbreviated lbf) and we used slugs for mass ( https://en.m.wikipedia.org/wiki/Slug_(mass) )
This shows engineering test models of Pathfinder, MER (Spirit/Opportunity), and Curiosity. It was taken in the Mars Yard at JPL, which engineered all three.
Yes, but it looks pretty tore up and the treads seem like they're coming completely off. I was under the impression that the wheels would have been built a little more sturdy. I know it's not the same, but car tires last for thousands of miles. So you would think that a hyper efficient tire, battle tested on earth terrain, would be designed to last at least 100. This is after 10 miles.
Edit: To clarify, I know they are thin and to save on weight. I just never thought it'd be designed to only last 20ish miles. Though another comment has said it will run fine without a lot of this material.
the wheel skin is 0.75mm thick, and was specifically designed to a goal of 10 to 20 km with the smallest weight possible: the rover mass is 899kg, the launch vehicle totals was 531000kg - by reversing the payload fraction one can see that for every gram of rover one needs more than half kilo of rocket to get it to mars, so there's that - you can get outside of your launch weight real fast.
this article has all the answers you're looking for:
short story - the wheel were tested to specification against expected rocks etc but once on the boogie suspension the front wheel had to support weight plus the force of the other wheel pushing, so there's where the extra punctures come from, this is what force was not accounted correctly.
