If the static friction between two surface X and Y is found to be 20 N, then the rolling between these two surfaces should most likely be :

Options

A. 25N
B. 20 N
C. 5 N
D. 50 N

Explanation

To solve the problem, we need to understand the relationship between static friction and rolling friction. Here are the steps to arrive at the answer:

### Step-by-Step Solution:

1. **Understand Static Friction**: We are given that the static friction between surfaces X and Y is 20 N. Static friction is the force that must be overcome to start moving an object at rest.

2. **Know the Relationship**: Rolling friction is generally less than static friction. This is because rolling objects do not have the same amount of surface contact and resistance as sliding objects do.

3. **Determine the Value of Rolling Friction**: Since static friction is 20 N, the rolling friction must be less than this value. Therefore, we can conclude that rolling friction < 20 N.

4. **Evaluate the Options**: If we have multiple-choice options, we need to identify which of them is less than 20 N. For example, if the options are:
- A) 50 N
- B) 30 N
- C) 5 N
- D) 15 N

We can see that the only values that are less than 20 N are C) 5 N and D) 15 N.

5. **Select the Correct Option**: Among the options that are less than 20 N, we need to select the one that is most likely to be the rolling friction. In this case, 5 N is a reasonable value for rolling friction compared to the others.

### Final Answer:
The rolling friction between surfaces X and Y should most likely be **5 N**.

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