The highest speed is where the slope is steepest this is the first line segment. time for a small airplane on a flight.ДЄ) What is the highest speed attained by the airplane on this flight? What was the runnerКјs average speed for the whole run, in m/sec?ДЄverage speed = total distance / time total distance is the sum of distances over each segment of time distance = speed Г— time also, donКјt forget, minutes have to be converted to seconds: 1st distance = 5 m/sec Г— (10Г—60) sec = 3000 m 2nd distance = 7 m/sec Г— (5Г—60) sec = 2100 m 3rd distance = 3 m/sec Г— (15Г—60) sec = 2700 m total distance = 3000m + 2100m + 2700m = 7800 m total time = (10 + 5 + 15) Г—60 sec = 1800 sec average speed = 7800 m / 1800 sec = 4.33 m/secД¤) The following plot shows the distance vs. time graphДЈ) A runner runs at a pace of 5 m/sec for 10 minutes, then 7 m/sec for 5 minutes, then slows to 3 m/sec for 15 minutes. time graph - Finding speed and average speed from a distance vs. Lab 9: Uniform Motion - Measuring average speed - Recognizing constant speed on a distance vs. (This is the amount of water the barge displaces.)Дensity = 1000 kg/m3 (from lab 8) mass = density Г— volume = 1000 kg/m3 Г— 500 m3 = 500,000 kg c) Subtract the mass of the barge from your answer in b) this is the remaining capacity of the barge in kg.ДҐ00,000 kg вЂ“ 20,000 kg = 480,000 kg d) Use your mass from c) and the density of steel to solve for the volume of the steel.ДЇirst, convert the mass to grams to get similar units: mass = 480,000 kg Г— 1000 g/kg = 480,000,000 g volume = mass / density = 480,000,000 g / 8 g/cm3 = 60,000,000 cm3 There are 1,000,000 cm3 in a m3, so this equals 60 m3.

Volume = (20 Г— 5 Г— 5)m3 = 500 m3 b) Using the density of water in kg/m3, find the mass of water the barge could hold. If steel has a density of 8 g/cm3, what is the maximum volume of steel can the barge hold without sinking? This can be done in steps: a) Find the volume of the barge in m3. Volumecopper = volumelead masscopper / densitycopper = masslead / densitylead masscopper / masslead = densitycopper / densitylead = 9.0/11.3 = 0.796Дў) An empty barge with a mass of 20,000 kg measures 20 m вњ• 5 m вњ• 5 m carries steel scraps.

Mass = 11.3 g/cm3 Г— (2 cm Г— 2 cm Г— 2 cm) = 90.4 gД¬opper cube: mass = 9.0 g/cm3 Г— (2 cm Г— 2 cm Г— 2 cm) = 72.0 g ratio = copper mass / lead copper mass = 72.0 g / 90.4 g = 0.796 (1/0.796 = 1.25 is also an okay answer, for the opposite ratio) The tricky (but short) way to do this problem: Recognize both volumes are equal and equate the volumes: Density = mass / volume The easy (but long) way to do this problem: Density = mass / volume lead cube: (Note the corrected typo above - you probably figured that out yourself though.) If you have a cube of lead 2 cm on each edge, and a cube of copper 2 cm on each edge, what would be the ratio of the masses of the 2 cubes? Lab 8: Force and weight Density - Measuring force and weight - Determining density - Relating mass, volume and density 1) Copper has a density of about 9.0 g/cm3.

A coppercube hasa volume of 5 cm3