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What is the temperature of the air leaving a bicycle pump when we want to inflate the tube to a pressure of 3 atm? Assume that the air entering the pump has temperature 20°C.

How would the power of sunlight hitting the Earth in aphelion change if we were to accelerate the Earth in the direction of motion in such a way to extend a year by a week? Estimate the temperature of the Earth in aphelion and perihelion if its heat capacity is almost zero. For simplicity assume that the original trajectory of the Earth was circular (not the case after the velocity boost).

Terka was playing around and spilled five liters of liquid nitrogen in her room. Couple days later she bought five liters of gasoline, brought it to her room and burned it. Could this playing around result in her being sick? To be more concrete describe the change in the temperature, pressure and oxygen concentration in her room (in both cases) if it is perfectly isolated and has dimensions 3$x3x4\;\mathrm{m}$.

Aleš stores toluen in a cylindrical bottle. When he left the room 90% of the bottle was occupied by toluen. When he returned after the weekend he noticed that the level of toluen was lower. He obviously accused his roommate from stealing. Then he realized that over the weekend the temperature in the room had risen by 20$\celsius$. Help: Aleš solve this mystery. Was his roommate really stealing or could the temperature rise be responsible? You can use data from http://en.wikipedia.org/wiki/Toluene (data page).

While enjoying his daily coffee, Lukáš decided to tune up his percolator a bit. He placed a bent tube with a short wire wrapped around it to the bottom of the main vessel (see the picture). The wire was placed height $d$ above the bottom and the vessel's water level was in a height $h$. Parameters of the tube were chosen in such a way that the water vapor created by boiling water close to the wire pushed the water above it. What is the power we need to provide to the wire in order to see water coming from the tube in a height $l?$

Massless rod of length $L$ is attached to an arch of top angle 2φ and radius $R$. A mass $m$ is glued to the rod's end (see picture). Assume that the body's motion is two-dimensional.

• Find the condition necessary for the system to be stable.
• What is the period of oscillations of the body about its equilibrium point?

Two travelers, one fat and the other skinny, are arguing who would have better chances of surviving in extreme conditions. Tell them who will live longer in the following environments. Hot(50 °C), cold(-1 °C), after a boat accident in the Mediterranean sea, inside a hurricane, inside a heavy snow storm and in the middle of earthquake inside a city. Except of their body fat they are exactly the same. They even wear the same clothes and they do not carry anything else. Be original and remember that details matter.

Returning home from an observatory, watching the sunrise, Janap discovered an easy way to calculate the temperature of the Sun. We do give away that the Earth is an absolute black body with a temperature of 0° C.

Construct a thermometer using the materials available at home. Base the calibration of the degree scale on well-known temperatures. Do not forget to attach a photograph of the end result of your efforts.

The movement of point mass is restricted on straight line by 2 end points. At the beginning the point mass $m$ is moving at speed $v$. The end point starts to move away at speed $v_{1}<<v$. How will the energy of point mass change?