**Complete Question**

A mass attached to a vertical spring causes the spring to stretch and the mass to move downwards. What can you say about the spring's potential energy Us and the gravitational potential energy Ug of the mass?

A. both Us and Ug decrease

B. Us increases and Ug decreases

C Both Us and Ug increase

D Us decreases and Ug increases

E Us increases and Ug is constant

**Answer:**

Option B is the correct Answer

**Explanation:**

The Gravitational Potential energy is mathematically represented as

Where m is the mass , g is the acceleration due to gravity while and h is the height

And in term of the spring this energy represents the workdone against gravitational Force

The Spring potential energy is mathematically represented as

Where k is the spring constant ans x is the extension in the spring

And energy represents the work that is being done to stretch the spring

If the system as state in the question is setup and is being increased then decreases