Question Solved1 Answer At the county fair, Chris throws a 0.15 kg baseball at a 2.4 kg wooden milk bottle, hoping to knock it off its stand and win a prize. The ball bounces straight back at 10 % of its incoming speed, knocking the bottle straight forward. Part A What is the bottle's speed, as a percentage of the ball's incoming speed? Express your answer using two significant figures. ΟΙ ΑΣφ ? (Ubottle); = (Ubaseball) % Problem 9.75 A 2.5 kg . 20-cm-diameter turntable rotates at 100 rpm on frictionless bearings. Two 200 g blocks fall from above, hit the turntable simultaneously at opposite ends of a diagonal, and stick. Part A What is the turntable's angular velocity, in rpm, just after this event? Express your answer using two significant figures. ΟΙ ΑΣΦ ? W= rpm

Suppose you are navigating a spacecraft far from other objects. The mass of the spacecraft is 4.0 104 kg (about 40 tons). The rocket engines are shut off, and you're coasting along with a constant velocity of ‹ 0, 26, 0 › km/s. As you pass the location ‹ 6, 8, 0 › km you briefly fire side thruster rockets, so that your spacecraft experiences a net force of ‹ 5.0 105, 0, 0 › N for 25 s. The ejected gases have a mass that is small compared to the mass of the spacecraft. You then continue coasting with the rocket engines turned off. Where are you an hour later? (Think about what approximations or simplifying assumptions you made in your analysis. Also think about the choice of system: what are the surroundings that exert external forces on your system?)

HW2.1. Finding the parametric solution Find the parametric solution of the following linear system: = -3 121 + 0x2 + 0x3 1x1 +-1x2 + 2x3 121 + 1x2 + 2x3 = -5 = -1 21= x1 { x 0% 22= X2 ? x 0% X3 = x3 ? 100% How to enter your answer: If you think that x1 = 2x2 + 3x3 + 5, then enter 2*x2 + 3*x3 + 5. If you think that X2 is free, then enter x2.

Case: - The population of a coal mining community mid-yearwas 8,700. - The number of new cases of lung cancer in this community between January 1 and June 30 (mid-year) \( =68 \). - The total number of cases of lung cancer as per the cancer registry in this community as of June \( 30=215 \). - The annual mortality rate in this community is \( 11.5 \) per Case: - The population of a coal mining community mid-yearwas 8,700. - The number of new cases of lung cancer in this community between January 1 and June 30 (mid-year) \( =68 \). - The total number of cases of lung cancer as per the cancer registry in this community as of June \( 30=215 \). - The annual mortality rate in this community is \( 11.5 \) per 1000 (higher than the national average). 62 people in this community died of lung cancer this year. Questions 4-10 are based on the case presentedabove. Show all work for calculations including formulas used. These are found in the power point presentation this week. 4. Calculate the incidence rate (per 1000 ) of lung cancer in this community for the 6- month period. 5. Calculate the prevalence rate of lung cancer per 1000 for this community June 30 6. Calculate the actual number of people in the community expected to die this year. 7. Calculate the disease specific mortality rate in this community for lung cancer. 8. Calculate the case fatality rate in percentage for lung cancer in this community.

242 Equipotential Surfaces and the Electric Field Two large, parallel conducting plates are 10.0 cm apart and have charges of equal magnitude and opposite sign on their facing surfaces. The plates are oriented so that an electrostatic force of 5.96 x 10-15 acts to the right on an electron placed anywhere between the two plates (Neglect fringing.) Find the magnitude of the electric field between the plates. Enter a positive number if the field points to the right and a negative number if the field points to the left. N c Save for Later Submit Answer

Parts E and B please 5. Compute the power Px and the energy Ex for each of the following signals: (a) x(t) = e-3tu(t) (b) x(t) = ej(2t+31/4) (c) x(t) = cos(t/2) (d) x[n] = (?)"u[n] (e) x[n] = ej(1/2+31/8) (f) x[n] = cos (31n/4)

1. Derive an expression for the horizontal distance of a vertical staff from a tacheometer if the line of sight of the telescope is horizontal 2. Derive expressions for the horizontal distance D and the vertical intercept (difference) V when the staff is (a) elevation and (b) depression. 3. The distance between a tachometer station and a staff station is measured to be 50.85 m. with the line of sight horizontal, the stadia hair readings are found to be 1.99 m and 1.395 m. Determine the instrument constant. 4. The following readings were taken with a tacheometer on to a vertical staff and zero vertical angle. Horizontal Distance Stadia Readings 46.2 m 0.78; 1.01; 1.24 51.2 m 1.86; 2.16; 2.47 Calculate the tacheometric constants. 5. The following readings were taken with tachometers on a vertical staff stand on three points, if the elevation the station point is 45.9 m and the height of instrument is 17.6 dm. Stadia readings Vertical angle 0.795, 1.025, 1.255 1.875, 2.180, 2.485 5 30 1.368, 2.359, 3.35 -6° 45' Find the distance from station to each staff point and their reduced levels? 6. In determining the elevation of point A and the distance between two points, A and B, a theodolite is set up at A and the following data are obtained: Z or a = 92° 45', stadia interval = 1.311m, hi = 1.28 m, and the line of sight at 2.62 m (central staff reading). The instrument constant K = 100 and C = 0.03 m. The elevation of B is 38.28 m. compute the distance AB and elevation of point A. 7. The elevation of station P is 345.67m. The height of theodolite over that station is 1.23m. When observing a rod held on station Q, the following data are recorded, Vertical angle - - 9° 45', lower staid hair = 0.83, center hair = 1.23, upper stadia hair = 1.63. Determine the distance between P and Q, and elevation of Q. 8. Stadia readings were taken with a theodolite on a vertical staff with the telescope inclined at a V.C.R of 93°30'. The staff readings were 299, 205 and 112 cm. The reduced level of the staff station is 100.75m, and the height of the instrument is 14 Dm. What is the reduced level of the ground at the instrument? Take constants as 100 and zero. 9. A tacheometer is setup at an intermediate point on a traverse course PQ and the following observations are made on a staff held vertical. Staff Station V.C.R + 279° 30' + 275900 Staff Intercept (S) Central Hair Readings 2.250 2.105 2.055 1.975 The constants are 100 and 0. Compute the length PQ and the reduced level of Q. if RL of P- 350.50 m. 10. From an instrument station Pof R.L 218.56 m two depressed lines of sight were taken to a staff held vertically over a station Q. The staff readings obtained is 3.160 m and 1.310m. The angels of depression of the lines of sight are 7 15 and 87. Find the horizontal distance between the two stations. Find also the R.L of the station Q. The height of instrument above the station P is 1.51m. 11. A theodolite was set over a station A of reduced level 44.620m, the instrument height being 1.425m. Observations were taken by tangent method to the 3m and 0.60m marks on each staff held vertically at three stations B, C and D with the following results. Instrument station Staff Station V.C.R 27910 885 95°15 273 30 9224 112 10 Find the distances from A to each station and their reduced levels? 12. Observations with a tachometer gave staff intercepts of 0.595m and 1.490m with telescope Horizontal and the staff held vertically at Horizontal distance of 61.062m and 152.40m respectively from the instrument, calculate the instrument constant and additive constant of the tachometer. The instrument was then set over a station with R.L 80.559m. the height of the instrument axis above the station point being 1.29 m. the readings of the three hairs on a vertical staff were 0.915m, 1895m and 2.875m, the telescope being inclined at 8 above the Horizontal. Determine the R.L of the staff station and its distance from the center the instrument.