Can someone guide me through this question from my AP Physics C homework?
Some European trucks run on energy stored in a rotating flywheel, with an electric motor getting the flywheel up to its top speed of 300 φ rad/s. One such flywheel is a solid, uniform cylinder with a mass of 280 kg and a radius of 0.829 m. (a) What is the kinetic energy of the flywheel after charging? (b) If the truck uses an average power of 7.9 kW, for how many minutes can it operate between chargings? I did this to get the my answer....which got marked wrong online. I=.5m(r^2) I=.5(280 kg)(.829 m)^2 I=962.1374 (m^2)kg KE=.5I(ω^2) KE=.5(962.1374 (m^2)kg)(300 rad/s)^2 KE=4,329.6183 J I know the second part of this problem would just be that answer divided by 7.9 kW, but I'm getting marked wrong on the first answer so I can't get that one either...is there something wrong with my equations/method to get the first answer? Thanks.
Can someone guide me on an essay?
Hi i have to write an assignment but i am unsure of what exactly to write about, could someone give me a point in the write direction as what to write about. These are the three things i have to write about. 2. Describe a network and relevant standards and protocols used for a modern programmable controller system (P7) a) Describe an Ethernet Network b) Draw up a table of Network Standards for Ethernet 3. Compare two different networks used for a modern programmable controller system (M3) a) Compare Ethernet Networks and Data Highway+ . Include in your discussion o Bandwidth or Baud Rate o Max Cable Distance o Devices supported 4. Compare the current capabilities and limitations of a programmable controller and identify possible areas of future development (D2) a) Investigate the latest PLC/Control Panel Technology b) Compare current capabilities with the latest PLC/Control Panel Technology c) Investigate the latest wireless Sensor Technology in PLCs d) Discuss advantages and disadvantages of wired Sensor Technology and wireless Sensor Technology in PLCs
Could someone guide me on this question?
The most obvious answer is that the doctors made a mistake 15 years ago and didn't remove the left ovary and right uterine tube and may have only remove them from the right or left side only. It will not be the first time doctors removed sometime from the wrong side of a body. Another possibility is she might have underwent in vitro fertilization.
Can someone guide me along this calculus question?
Near a buoy, the depth of a lake at the point with coordinates (x, y) is z = 200 + 0.02x^2 - 0.001y^3, where x, y, and z are measured in meters. A fisherman in a small boat starts at the point (80, 60) and move toward the buoy, which is located at (0, 0). Is the water under the boat getting deeper or shallower when he departs? Explain.
Can someone guide me through this problem?
This problem basically comes down to a series of three conversions first you have to convert the number of grams of CaH2 you start with to figure out how many moles of CaH2 that is equal to. One mole of CaH2 has a mass of has a mass of 42.09 grams (the sum of one Ca and 2 H's) 1st conversion 50.0 g CaH2 x (1 mole CaH2/42.09g) = moles CaH2 Then you have to convert the number of moles of H2 that could be produced from the reaction, for this you use the ratio of substances (coefficients) from the balanced equation. One mole of CaH2 and 2 moles water produce one mole of Ca(OH)2 and 2 moles H2. 2nd conversion moles of CaH2 (from above) x (2 mol H2/1 mol CaH2) =moles H2 this is basically multiplying by 2 but understanding why is the important part. finally, now that you have mol H2 you have to multiply by it's molar mass 2.02 g/mol to find the mass of H2 3rd conversion, mols H2 x (2.02 gH2/ 1mol H2) =g H2 I don't have a calculator around but if you do this all together you get 50 x(1/42.09) x (2/1) x (2.02/1)= this should be pretty close to five as your numerator is about 200 (50x2x2) and the denominator is just more than 40