Question An unfortunate astronaut loses his grip during a spacewalk and finds himself floating away from the space station, carrying only a rope and a bag of tools. First he tries to throw a rope to his fellow astronaut, but the rope is too short. In a last ditch effort, the astronaut throws his bag of tools in the direction of his motion, away from the space station. The astronaut has a mass of ?a=113 kg and the bag of tools has a mass of ?b=10.0 kg. If the astronaut is moving away from the space station at ?i=2.10 m/s initially, what is the minimum final speed ?b,f of the bag of tools with respect to the space station that will keep the astronaut from drifting away forever?

A uniform sphere of mass m = 0.85 kg and radiu r = 4.2 cm is held in place by a massless rope attached to a fricionless wall a distance L = 8.0 cm above the center of the sphere. What is the tension in the rope in N. Note that the sphere may rotate against the wall so that the contact point of the rope is not exactly over the sphere center. L R

Please help solving problem 1,2 and 3. Thank you very much. For questions 1 - 3, consider the following test results obtained for a surface water sample. lon Concentration (ppm) Ca2+ 36.0 Mg2+ 10.8 Na 12.4 K 5.9 нсоз" 82.1 SO42 32.0 CI 16.9 NO3 7.4 1. Check the accuracy of the analytical measurements. Do you suspect that a constituent of significance has been neglected? If so, is it a cation or an anion? 2. Determine the mole fraction of calcium, magnesium, and sulfate for the water sample given above. 3. Determine this water's hardness and alkalinity in mg/L as CaCO3.

Die-rolling experiment: 1) Acquire any "fair-enough" die. 2) Roll it at least 100 times (each person for themselves). 3) Note what the outcome is overy time. 4) For each group of 5 (go consecutively, i.e. group first five rolls, then the next five rolls, etc.), take the average of the 5 rolls. For example, if the first five rolls are \( 3,6,1 \), 5 , and 3 , Die-rolling experiment: 1) Acquire any "fair-enough" die. 2) Roll it at least 100 times (each person for themselves). 3) Note what the outcome is overy time. 4) For each group of 5 (go consecutively, i.e. group first five rolls, then the next five rolls, etc.), take the average of the 5 rolls. For example, if the first five rolls are \( 3,6,1 \), 5 , and 3 , the average will be \( 18 / 5=3.6 \). 5) You will end up with at least 20 averages. Plot these averages on a \( 2 \mathrm{D} \) column graph. Alternatively, you can do a histogram of your results, which will be a fancier way of doing a 2D column graph. With a histogram though, you can control the bin size and instead of each individual average (e.g. 3.2, 3.4. 3.6, etc.). you can group them together with a bin size of 1 . Bonus credits will be assigned to those showing their results with a histogram of bin size 1 in addition to their regular \( 2 \mathrm{D} \) column graphs. 6) All the probabilities of \( 1,2,3,4,5 \) and 6 are \( 1 / 6 \) with a fair die. Therefore, the probabilities are said to be "uniformly distributed". Then, why is your \( 2 D \) column graph / histogram not looking uniform at all? Speculate / comment on the rationale for this.

Units V.C represents which quantity? Select one: a. Electric potential energy, U b. Electric Constant, k c. Electric Potential d. Electric Flux, F e. Electric Field, E

2-4 Estimate the TDS for one of the water samples in Problem \( 2-1 \) or \( 2-2 \) (to be selected by instructor) using Eq. (2-11) and by summing the mass of the individual ionic species. How do the computed values compare?The following test results were obtained for three treated wastewater effluent samples. Check the accuracy of the analytical 2-4 Estimate the TDS for one of the water samples in Problem \( 2-1 \) or \( 2-2 \) (to be selected by instructor) using Eq. (2-11) and by summing the mass of the individual ionic species. How do the computed values compare?The following test results were obtained for three treated wastewater effluent samples. Check the accuracy of the analytical measurements for one of the waters (to be selected by instructor). Do you suspect that a constituent of significance has been neglected? If so, is it a cation or anion? Determine the mole fraction of \( \mathrm{Ca}^{2+}, \mathrm{Mg}^{2+} \), and \( \mathrm{SO}_{4}^{2-} \) for one of the following treated wastewater effluents (to be selected by instructor).

Which of the following statements is correct regarding Kepler's three laws of planetary motion? Angular momentum of any planet about an axis through the Sun and perpendicular to the orbital plane is not invariant during its motion. Planets move in elliptical orbits with the sun not being at its center. Orbital period of a planet is directly proportional to Which of the following statements is correct regarding Kepler's three laws of planetary motion? Angular momentum of any planet about an axis through the Sun and perpendicular to the orbital plane is not invariant during its motion. Planets move in elliptical orbits with the sun not being at its center. Orbital period of a planet is directly proportional to its distance from the sun. Kepler's laws are valid only for planets in the solar system.