Explanation:
1)observation is that the light doesn't reach some parts of the points of interest
2)this is because the rays of the light were interrupted by different objects thus making the light divert different ways.
The answer is obviously d
Answer : The change in internal energy is, 900 Joules.
Solution : Given,
Heat given to the system = +1400 J
Work done by the system = -500 J
Change in internal energy is equal to the sum of heat energy and work done.
Formula used :

where,
= change in internal energy
q = heat energy
w = work done
As per question, heat is added to the system that means, q is positive and work done by the system that means, w is negative.
Now put all the given values in the above formula, we get

Therefore, the change in internal energy is 900 J.
The change in internal energy depends on the heat energy and work done. As we will change in the heat energy and work done, then changes will occur in the internal energy. Hence, the energy is conserved.
The error that would make the calculated density of the solid have if the material had a hollow center is that the calculated density would be low, because the volume would be incorrectly measured high.
<h3>What is density?</h3>
The measure of how densely a material is packed together is called density. As the mass per unit volume, it has that definition. Density Formula: = m/V, where is the density, m is the object's mass, and V is its volume. Density Symbol: D.
If a substance had a hollow center, its volume would be high and its density would be low.
Therefore, the error that would make the calculated density of the solid have if the material had a hollow center is that the calculated density would be low, because the volume would be incorrectly measured high.
Learn more about density on:
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