A system absorbs 400 J of heat and does work equivalent to 150 J on the surroundings. Calculate the change in the internal energy of the system.

Explanation

To solve the problem, we will use the first law of thermodynamics, which states that the change in internal energy (ΔU) of a system is equal to the heat added to the system (Q) plus the work done on the system (W).

### Step-by-Step Solution:

1. **Identify Given Values**:
- Heat absorbed by the system (Q) = 400 J
- Work done by the system on the surroundings (W) = -150 J (Note: Work done by the system is taken as negative)

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