• Why are two adjacent door mirrors not reflecting as one?

    So I have two door mirrors that I ve removed the frames from (both From the same company) and hung them side by side touching. Why aren t the combined mirrors reflecting evenly as one? Instead when standing in front of where they touch, my reflection is widened and basically not matching. I hung them perfectly... show more
    So I have two door mirrors that I ve removed the frames from (both From the same company) and hung them side by side touching. Why aren t the combined mirrors reflecting evenly as one? Instead when standing in front of where they touch, my reflection is widened and basically not matching. I hung them perfectly side by side touching.
    6 answers · 4 days ago
  • Physics Question - Current in Resistor of parallel circuit - Need Help!?

    Physics Question - Current in Resistor of parallel circuit - Need Help!?

    Best answer: The three R's in parallel are equivalent to 1/R = 1/5 + 1/12 + 1/20 1/R = 0.2 + 0.083 + 0.05 = 0.333 R = 3 Ω add 9 in series to get 12 Ω I = e/R = 9/12 = 0.75 amp that produces a voltage across the 3 in parallel of E = IR = 0.75 x 3 = 2.25 volts and the currents in the 3 branches are I = E/R I = 2.25/5 =... show more
    Best answer: The three R's in parallel are equivalent to
    1/R = 1/5 + 1/12 + 1/20
    1/R = 0.2 + 0.083 + 0.05 = 0.333
    R = 3 Ω

    add 9 in series to get 12 Ω

    I = e/R = 9/12 = 0.75 amp

    that produces a voltage across the 3 in parallel of
    E = IR = 0.75 x 3 = 2.25 volts

    and the currents in the 3 branches are
    I = E/R
    I = 2.25/5 = 0.45 amp
    I = 2.25/12 = 0.1875 amps
    I = 2.25/20 = 0.1125
    (the three should add up to 0.75 amps)

    PS, the circuit is drawn poorly, the junctions have to be shown clearly, see below.
    4 answers · 2 days ago
  • Is loudspeaker a motor or a generator?

    10 answers · 6 days ago
  • If friction causes a cart to speed up, when there is no longer an Fa, why does friction also slow it down? and how?

    Best answer: The cart is actually undergoing a "collision" with the earth. Nothing can speed up or slow down without a force. Friction between the tyres and the earth provide the force needed to accelerate the cart. Energy is still required and that comes from elsewhere. Friction between the tyres and the earth... show more
    Best answer: The cart is actually undergoing a "collision" with the earth.
    Nothing can speed up or slow down without a force.

    Friction between the tyres and the earth provide the force needed to accelerate the cart. Energy is still required and that comes from elsewhere.
    Friction between the tyres and the earth provide a force needed to slow the cart. Without this the cart would skid uncontrollably and brakes cannot work.

    There are other frictions that work the entire time.
    Friction between the air and the cart always slows it down.
    Friction between the axles and the bearings always slows it down.

    There are many different places where friction is involved.
    But the only friction that USES energy is one where two surfaces move relative to each other.
    To a large extent this is not true about the tyres on the road. They roll but do not slide.
    So this friction is not consuming much energy ( the only movement is due to the flex of the tyres. There is no movement between the tyre and the road ).

    OK. Now all these OTHER frictions use energy. Unless the engine is adding energy then it must come from the loss of kinetic energy. ie the cart slows down unless it is powered.

    Yet the friction between the tyres and the road actually pushes the car forward the entire time that the vehicle is being powered.
    4 answers · 3 days ago
  • Where can I find an X-ray of the human hand?

    I am needing a graphical X-ray of the tendons and muscles in the human hand. Where can I find such an image?
    I am needing a graphical X-ray of the tendons and muscles in the human hand. Where can I find such an image?
    8 answers · 6 days ago
  • I need help with these questions?

    1. A car travelling at a speed of 60 km/hr reaches its destination in ¼ hour. How much distance did it travel? 2. A boy runs at a speed of 8 metres per second. How long does he take to cover a distance of 1 km? 3. A boat is rowed at a speed of 5 km/hour. How much time will it take to row a distance of 40 km? 4. The... show more
    1. A car travelling at a speed of 60 km/hr reaches its destination in ¼ hour. How much distance did it travel? 2. A boy runs at a speed of 8 metres per second. How long does he take to cover a distance of 1 km? 3. A boat is rowed at a speed of 5 km/hour. How much time will it take to row a distance of 40 km? 4. The average speed of an Express train between New Delhi and Kota is 95 km per hour. The train take 5 hours to travel from New Delhi to Kota. Find the distance between New Delhi and Kota. 5. An aeroplane takes 3 hours to travel a distance of 3300 km. Another aeroplane travels at a speed which is 100 km per hour less than first aeroplane. How long will it take to travel the same distance by the second aeroplane? 6. Find the distance between two stations if a train travelling non-stop at 75 km/hour covers the distance between the stations in 20 minutes. 7. Two sprinters run the same race of 100 metres. One runs at a speed of 10 meters per second and the other runs at 8 meters per second. By what time will the first sprinter beat the other sprinter? 8. Aaron cycles from one place to another place at a speed of 7 km per hour. He cycles from 1015 hours to 1445 hours. Find the distance between these two places. 9. Victoria runs at 9 m per second. How much distance does she run in 2 minutes 30 second? 10. Ryan runs at 10 m per second. He runs for 5 minutes 10 seconds. What is the distance covered by him.
    6 answers · 6 days ago
  • Quantum computer vs classical computer application difference?

    Best answer: Tape and disk based core storage was replaced with magnetic ferrite disk core storage. That was replaced by transistor boards, which was replaced by integrated circuits. We have had static memory and dynamic memory. Memory has grown from less than 1k up to Gigabytes. Yet the differences to the user are only the... show more
    Best answer: Tape and disk based core storage was replaced with magnetic ferrite disk core storage.
    That was replaced by transistor boards, which was replaced by integrated circuits.
    We have had static memory and dynamic memory.
    Memory has grown from less than 1k up to Gigabytes.

    Yet the differences to the user are only the differences we get from having MORE of it.
    The same has happened in our processing units. From the valves of ENIAC. To transistor boards to integrated circuits to the megalithic processor.

    A whole NEW layer has been added. Microcode. So that the hardware is separated from the machine code level.
    Which makes it possible for a manufacturer to change the underlying hardware without anyone altering their compilers at all.

    The push for nearly 30 years has been compartmentalization. In most applications today we use higher level languages than Pascal, C, Fortran, Algol, Cobol etc.
    These languages include things like Java. But on top of those we build Android. On top of that we build a browser for which we program APPS.
    So in fact most people are working three levels more remote from the hardware than they were 30 years ago.

    Some people need to work at the machine level of course.
    But most people have no need to understand the vagaries of hardware.
    Hence when you talk of applications, at this level it really wouldn't matter if your computer was simply a team of slaves or an electronic device. You do the same things and get the same results.

    That is what the whole design of computers has been about for decades. It is not likely to change over the next few decades.
    4 answers · 4 days ago
  • What is the velocity of the fluid through the narrow part of the pipe?

    Best answer: a) conservation of mass m₁ = m₂ ρ Q₁ = ρ Q₂ Q₁ = Q₂ v₁ A₁ = v₂ A₂ v₁ π/4 D₁² = v₂ π/4 D₂² v₁ D₁² = v₂ D₂² v₁ = v₂ (D₂/D₁)² v = 0.270 (40.8 / 5.81)² v = 13.3 m/s b) Bernoulli's principle P₁ + ½ ρ v₁² + ρgh₁ = P₂ + ½ ρ v₂² + ρgh₂ 1.738 kg/L = 1738 kg/m³ 1.59 atm = 1.61×10^5 Pa P₁ + ½ (1738) (0.270)² + 0 =... show more
    Best answer: a) conservation of mass
    m₁ = m₂
    ρ Q₁ = ρ Q₂
    Q₁ = Q₂
    v₁ A₁ = v₂ A₂
    v₁ π/4 D₁² = v₂ π/4 D₂²
    v₁ D₁² = v₂ D₂²
    v₁ = v₂ (D₂/D₁)²

    v = 0.270 (40.8 / 5.81)²
    v = 13.3 m/s

    b) Bernoulli's principle
    P₁ + ½ ρ v₁² + ρgh₁ = P₂ + ½ ρ v₂² + ρgh₂

    1.738 kg/L = 1738 kg/m³
    1.59 atm = 1.61×10^5 Pa

    P₁ + ½ (1738) (0.270)² + 0 = (1.61×10^5) + ½ (1738) (13.3)² + 0
    P₁ = 3.15×10^5 Pa
    P₁ = 3.11 atm
    4 answers · 4 days ago
  • Whether travel in time (based on the existence of a person in two time) violate the principle of material survival?

    Best answer: Yes probably. If you remember the end of Back to the Future, Marty returns from the past in time to see himself jump in the Delorean. There are two Marty McFlys ... if the universe allowed this you could keep copying people or objects which would violate conservation of mass/energy! But although travelling forward... show more
    Best answer: Yes probably. If you remember the end of Back to the Future, Marty returns from the past in time to see himself jump in the Delorean. There are two Marty McFlys ... if the universe allowed this you could keep copying people or objects which would violate conservation of mass/energy!

    But although travelling forward in time is allowed (you just need to travel close to light speed so your clocks tick slower than in the frame of reference you started from), travelling backwards in time seems impossible. This is because you need an infinite amount of energy to get to light speed let alone go faster than light to travel back in time. So the universe seems to have a built in mechanism to stop such things!

    It is possible for quantum particles to move forwards and backwards in time, but only over very small amounts consistent with the Heisenberg uncertainty principle. They're tiny amounts that suggest space and time at a quantum scale is a bit fuzzy.
    5 answers · 6 days ago