What is Clock: Definition and 483 Discussions

CLOCK (Circadian Locomotor Output Cycles Kaput) or Clock is a gene encoding a basic helix-loop-helix-PAS transcription factor that is believed to affect both the persistence and period of circadian rhythms.
Research shows that the CLOCK gene plays a major role as an activator of downstream elements in the pathway critical to the generation of circadian rhythms.

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  1. C

    Is There a Safe Chemistry Clock Experiment for Kids Involving Only Water?

    I would like to do a chemistry expermient for kids. I would like to perform the chemistry clock experiment with harmless materials. Does anyone know if there is a version of the chemistry clock experiement where you simply add water to a solution to initiate the color change reaction? Thanks in...
  2. G

    Need help converting battery clock to DC

    I have a clock that eats up the batteries it runs on pretty quickly, and so I would like to convert it to run on DC power. The clock has a total of 2 D batteries, 1 in each "foot" of the clock (they are separate). There is a white wire that starts at the + side of one battery, goes over to...
  3. T

    Understanding Clock Counter Complementing in Digital Circuits

    i understood that each time a digit complements and complements the next digit etc.. but i can't see how it works because if its truee then from the 0000 state by one pulse we will have 1111 i can't ubderstand how we get the numbers between here is circuit...
  4. Phrak

    How Does a Clock Measure Time?

    It is certainly within the realm of rational scientific inquiry to ask, not simply what a clock measures, but it what manner it measures. These are contextual to an experimental science. 1) In common to all clocks, how do clocks measure time? 2) Are there any clocks (that one actually...
  5. E

    Clock Synchronization Techniques Using 555 Timer for Accurate Results

    Hi there, I have a clock at the receiver and I want it to be synchronized with the transmitter clock. For this reason, I send a short pulse to the receiver so that I know when a clock transition has to start. For the clocks I'm using the 555 timer. So far I tried experimenting with the...
  6. petm1

    Is Time Dilation a Result of Matter's Intrinsic Motion?

    All clocks measure the intrinsic motion of matter using a counter to assign a number to the present at the arbitrary rate of one per second. This allows us with a calendar, a circular table or chart, to relate to the past and plan for the future. This makes me wonder about matter, and how it...
  7. morrobay

    Elapsed time on accelerating clock

    Consider three clocks A,B and C all set at t=0 at t=0 Clock A is stationary on earth Clock B is on a rocket at a distance of 16.43 (10^14) meters away from Earth and accelerates instantaneously to .6c and arrives at earth. Clock A time = 105.6 days. Clock C is on a rocket at a...
  8. B

    Conventionality and clock symchrnization

    Please tell me if "conventionality of dimultaneity" and "Einstein clock synchronization" are one and the same thing? Please tell me how could be quoted ideas received on the Forum.
  9. B

    Non-standard clock synchronization

    Selleri proposes the following transformation equations x=g(x'-vt') t=t'/g g=gamma. Einstein's clock synchronization requires t(E)=t(e)+x/c t(E) reading of a clock located at a distance x from the origin, t(e) reading of a clock located at the origin when the synchronizing light signal is...
  10. E

    The light clock and time dilation.

    How do you argue that the equation for time dilation derived from studying a light clock can be used in general. For instance, how does it tell us that a mechanical clock would also show time dilation?
  11. M

    Reading of a pendulum clock from the earth to the moon

    A certain pendulum clock that works perfectly on Earth is taken to the moon, where g = 1.62 m/s^2. Acceleration of gravity is 9.81 m/s^2 on Earth. THe clock is started at 12:00:00 AM and runs for 22 h. What will be the reading for the hours on the moon? answer in h T = 1 second g = 9.81...
  12. L

    Circular motion of a clock

    The problem statement a) for a clock with minute hand 20 cm long find the average accelration of the hand as it moves from the 4 position to the 8 position b)an amusement ride is a rotating cylinder where the person is plastered to the inside wall as the ride speeds up and the floor drops...
  13. B

    Clock Synchronization: Teaching Special Relativity

    Please tell me if it is compulsory to start teaching special relativity with describing the clock synchronization procedure? Which is the best way to do it in your opinion? Thanks
  14. S

    Time dilation and the photon clock

    Hello, I just baught my next set of textbooks and started reading about relativity. In one of the books it uses the example of a two clocks who "tick" every time a photon it emitted hits the mirror and returns to the sensor. It demonstrated that, if the box containing this clock is moving, it...
  15. M

    Atomic clock - optical pumping

    I am doing some research on atomic clocks. From what I have read, I understand that in Rb atomic clocks you: -optically pump a cell of Rb, so that the electrons are all in a single hyperfine state -subject the cell to microwaves of appropriate frequency, so that the electrons will be...
  16. M

    Grandfather's Clock - Nonlinear Pendulum

    Homework Statement A Grandfather's Clock is adjusted to keep perfect time if the amplitude is 2 degrees. How many seconds does it lose or gain in a year if instead the amplitude is 10 degrees. Homework Equations T/4 = integral from 0 to qmax = dq/\sqrt{2E-q^2 - \epsilon/2*q^4} where q...
  17. P

    Time When Pendulum Clock is Put on Moon?

    A pendulum clock that works perfectly on Earth is taken to the moon where g = 1.63 m/s^2. If the clock is started at 12:00 A.M., what will it read on the moon 24 Earth hours? The equation you would probably use is T = 2(pi)(sq. root of m/k) Can someone get me started?
  18. K

    Solving for Time Gain in Pendulum Clock Covered by Lead Layer

    Homework Statement A pendulum clock in the centre of a large room is observed to keep correct time. How many seconds per year will the clock gain if the floor is covered by a 1m thick layer of lead of density 11350kgm^-3 ? Newtons gravitational constant is G = 6.67 x10^-11 Nm^2 kg^-2...
  19. H

    How Is the Angular Momentum of a Clock's Second Hand Calculated?

    [SOLVED] Angular Momentum Homework Statement Find the magnitude of the angular momentum of the second hand on a clock about an axis through the center of the clock face. The clock hand has a length of 15.0cm and a mass of 6.00g. Take the second hand to be a slender rod rotating with...
  20. S

    GPS Clock After One Year: Time & Relativistic Effects

    Suppose i have two clocks on Earth showing 12:00 hours. After, one of the clocks is put in a gps satellite for a year. After one year that clock returns to earth. Due to relativistic effect what time that clock shows? Less than 12:00? If so why?
  21. D

    Reconfiguring your biological clock

    I posted this on Academic and Career Guidance, but got 0 replies. So I'll repost it here and see if anyone can offer any help: I'm an engineering student in my first year. I find that I am most productive and and best able to concentrate at night. And not just at any time of night, but like...
  22. D

    Reconfiguring your Biological Clock

    I'm not sure where this thread should actually belong, either in General Discussion or here, but I'll post it here and leave the mods to move it if it's inappropriate. I'm an engineering student in my first year. I find that I am most productive and and best able to concentrate at night...
  23. C

    What are the approximate costs for operations on common x86 chips?

    As a first step to optimizing code, I like to think about faster ways to do things. Algorithmic improvements are far better than minute improvements to code, or even use of inline assembly, in general. But most optimizations beyond common subroutine elimination and its ilk substitute...
  24. B

    Is Clock Synchronization Truly Possible According to Einstein's Theory?

    Consider the clocks C(0)(x=0,y=0) ticking and clock C(x,y=0) stopped and fixed to read t=x/c. Source S(0,0) emits a light signal towards clock C. Arriving at its location the light signal starts clock C and we say that C(0) and C(x,0) are synchronized a la Einstein. Is there something wrong in...
  25. C

    DCM (Digital Clock Manager)

    I am tasked to use the DCM in Xilinx's architecture wizard. Can anyone explain what is the function of a DCM and how does it actually work? What are the inputs and outputs of a typical DCM? many thanks!
  26. S

    Creating a Distance-Aware Clock Software

    I m going to create a new clock software which can change its time with respect to distance and direction. Suppose if a person is in India and he starts his journey off towards london.suppose he starts at 7:00 am(ist). suppose it takes him 8 hrs to reach london. so after reaching london hic...
  27. T

    A question about a relativity light clock

    I'm learning about relativity and how going close to the speed of light can distort time, but I have questions/need for confirmation on a few things. After seeing a little video about I thought of some things and came to a few logical conclusions. Okay. A light clock as seen at...
  28. J

    Clock Ticking Speed: Center vs Surface

    How fast would a clock tick at the center of the Earth compared to one on the surface?
  29. O

    GPS, GR, satellites and clock speed on the satellites

    I am looking over the Project A: Global Positioning System is Exploring Black Holes; introduction to General Relativity by Taylor and Wheeler. At first, they convincingly suggest that the time dilation caused by the differences in radius from Earth clocks to the satelight clocks will cause the...
  30. B

    Clock synchronization problem

    Is it possible to realize a situation in which all the synchronized and ticking clocks of a given inertial reference frame read a zero time? Thanks
  31. B

    Radar echo and clock synchronization

    Please help me in the folowing problem: It is well known that the radar echo (police radar) establishes a relationship between the period T(e) at which a stationary observer emits successive light signals and the period T(r) at which he receives them back after reflection on an object that...
  32. B

    Is clock synchronization compulsory

    Working with clocks we have to perform an initialization (to ensure that when the origins of the involved inertial reference frames are located at the same point in space theirs clocks read t=t'=0) and a synchronization of the clocks of the same inertial reference frame ensuring that they...
  33. S

    Light Clock Experiment Flawed?

    Hi - I’m new here and I'm probably a bit of an impostor in that I’m not a physicist, scientist or even academic. I’ve been trying to increase my understanding of Relativity and often see a light clock experiment that is used to demonstrate time dilation. Given the extent that this particular...
  34. S

    Timekeeping Changes with Temperature: Pendulum Clock at 1°C

    An aluminum clock pendulum having a period of 1.20 s keeps perfect time at 20.0°C. When placed in a room at a temperature of 1°C, how much time will it gain every hour? I used T=2pi*squareroot(x/9.8) and solved for x to be .357823847 as the length of the pendulum. Then I plugged that into...
  35. L

    Why was Lorentz transformation known before Einstein explained clock synchronisation

    The constancy of the speed of ligth is a result of the Maxwell's equations. And the Lorentz transformation is an invariance of Maxwell's theory that was known before the special theory of relativity was discovered. Why and how did the physics of the 19th century (particularly Maxwell) built...
  36. M

    A moving clock lags behind a stationary clock

    A. Einstein states the following on page 49 in The Principle of Relativity: "Between the quantities x, t, and T, which refer to the position of the clock, we have evidently, x = vt and T = (t - v*x/c^2)/sqrt(1 - v^2/c^2). Therefore, T = t*sqrt(1 - v^2/c^2) = t - (1 - sqrt(1 -...
  37. N

    Max Clock frequency with a Flip-Flop

    I need to know the max clock frequency of two identical J-K flip flops linked together (the first flip flop has HIGHs running into its inputs, and the second flip flop has the outputs (Q and Q bar) running to its inputs). They share a common clock. The data sheets say the prop delay (low to...
  38. M

    Circular motion - pointers of a clock

    (a) What's the time between 9h and 10h in which the minute and hour pointers are equal? (b) After midday, what's the first time in which the three pointers are equal? For (a), I tried to do: \Theta = \Theta_0 + \omega_{hours} \cdot t \omega = \frac{2 \cdot \pi}{T} \Theta_0 = 270^o...
  39. B

    Reworking a TIX Clock - Get Help Here!

    Hello, I have a strange question. I have a TIX clock and would like to basically enlarge it. So I'd like to take the controller card off of the TIX board << link to cuberoot.com removed by berkeman -- possible virus issues >> and create a new board that will support these...
  40. B

    Clock Synchronization: Einstein's Procedure & Others

    is it correct to state that all the clocks of a given inertial reference frame, synchronized in accordance with Einstein's synchronization procedure display the same running time? Do you know other synchronization procedures which lead to the same result? sine ira et studio
  41. B

    Light clock and teaching of special relativity

    do you think that the light clock is a good pedagogical tool for introducing special relativity? a teacher of mine told us that there is no advantage without disadvantage! sine ira et studio
  42. E

    Shollenbarger's Clock: Proving No Time Exists Where Hands Equidistant

    Shollenbarger's Clock: Excluding 12:00, Is there ever a time on a clock where the second, minute and hour hands are equidistant from each other? (In other words, the three hands are all 120° apart? If yes, give the EXACT time(s) that this occurs. If no, prove that no such time exists. Good Luck!
  43. D

    Exploring Light Clock Motion: An Analysis

    This question is not directly related with time dilation as much it is with the light clock that is so often used to improvise the concept of time dilation. This clock consists of two mirrors placed parallel to each other, a light blip that bounces between the mirrors. The light blip is...
  44. R

    Special Relativity Clock Challenge

    Here's the question from my text: "Alice and Bob are movin in opposite directions around a circular ring of radius R, which is at rest in an inertial frame. Mobh move with constant speeds V as measured in that frame. Each carries a clock, which they synchronize to zero time at a moment when...
  45. G

    Simple harmonic motion of clock

    let us consider a bob suspended by means of a thread from a fixed point (wrt ground and i m considering ground to be an inertial frame in this problem ) . What will be the time period of small oscillations of this pandulum as seen by a man accelerating with an acceleration a along the horizontal...
  46. K

    Solving the Ladybug's Clock Puzzle: Unraveling the Mystery

    Ok here is what the problem states in the book "A ladybug settled onto the tip of a clock's minute hand. The minute hand is 12ft long. How far does the ladybug travel from 3:00pm to 3:20pm?" I figured there are 30 degrees to every hour (divide 360 by 12). Then the 20 minutes would...
  47. A

    Exploring Time Travel: Could We Rewind the Clock?

    We all know by Einstein's Special Theory of Relativty that when an objects at the speed of light, it could move foward in time quicker than the other people. However, I was wondering. Is time travel possible for going back into the past? Can we rewind time as if any two oppposites in nature...
  48. H

    Exploring the Mathematics of Water Clocks

    Hi all! I'm finding information about the ancient time counting machine --- water clock, as shown in the figure. I know that the water clock invented by Ktesibios has a self-regulating ability. This is achieved by a float. Anyone got more information about the mathematics involved?
  49. D

    Clock synchonization in relativity

    I'm a bit confused about a statement in my course on relativity. I have a system S' that is moving with a direction v (in the x'-direction) compared to the system S, so the following transformation formula holds: t = gamma*(t'+vx'/c^2) The textbook now goes on to say (translated from dutch...
  50. W

    Can red shift compare which clock go faster?

    Hi, We often say, an observer near the horizon of a BH finds the light traveling from far outside the horizon blue shifted, or an observer away from the BH finds the red shift of light from near the horizon. We get a conclusion that a clock near the horizon goes faster than a clocker far...
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