(Originais Teachy 2023) - Question Easy of Physics

A person with height $$\boldsymbol{h}$$ stands in front of a pinhole camera in order to produce an image on the opposite side of the camera that corresponds to three quarters $$(3 / 4)$$ of their height. Knowing that the pinhole camera has a depth $$\boldsymbol{d}$$, what will be the distance between the person and their image?

Your image O' and five observers: 1, 2, 3, 4, 5. Which alternative presents only the observers who see the object reflected in the mirror?

João is helping his father fill the home pool, which is rectangular and has the following dimensions: 8 meters in length, 4 meters in width, and 1.5 meters in depth. They are using a hose with a constant flow rate of 20 liters per minute. Considering that the pool was completely empty and there was no water wastage in the process, answer: (a) What is the total volume of the pool in liters? (b) How long, in hours, will it take to completely fill the pool with the hose? (c) If the water in the pool had the mentioned constant flow rate, but drained through an opening of the same size as the hose, how long would it take for the pool to completely empty?

In an experiment conducted in the Physics Laboratory, a group of students found that a wooden block floated in water with half of its volume submerged. Next, the same block was placed in oil where they found that it floated with $$\frac{1}{4}$$ of its volume emerged. From this information, we can affirm that the specific mass of the oil is: