How to Join Similar Fields Based on a Third Field?

[Inaccessable]

I'm new to Access and I'm sorry if this is something very simple.
I have been having trouble figuring out how to assign specific numbers to a field based on the ID and another table holding the corresponding values through the use of queries.

Table1 has a field that has three fields, the first being ID, the second being item description, and the third being an empty field for weight.
Table2 has a two fields, the first being the ID, and the second being weight values that correspond to that ID.



The purpose of the query is to assign values to the empty weight field in table 1 by assigning a weight value of the matching ID in table 2.

Here's an example:

Table 1
ID          Description  Weight
2000001  Obj 1
2000002  Obj 1 Blue
2000003  Obj 3 

Table 2
ID          Description  Weight
2000003  Obj 3           1.2
2000001  Obj 1           3.5
2000002  Obj 1 Blue      .4
2000004  Obj 5           .25

After the query:
Table 1
ID          Description  Weight
2000001  Obj 1           3.5
2000002  Obj 1 Blue      .4
2000003  Obj 3           1.2

Again, I am quite new to access, and information I have found insofar has not been sufficiently helpful. Any help will be met with much gratitude.

[June7]

Is it really necessary to actually save the weight to Table1? You could just do a query that joins Table1 and Table2. Isn't even necessary to have the Description in Table1. Are there other fields in Table1? What is purpose of these two tables?