# Search results

1. ### I Reference for measuring the speed of of light

(Sorry, my questions may look irrelevant but complete my thoughts) So, every moving object has its own time frame which appears to move slower than every other time frame. i.e. there is no absolute point in time. So, which frame do we refer to when we say that the universe is 14 billion years old?
2. ### I Reference for measuring the speed of of light

Thanks! I will read about the relativity of simultaneity as soon as I can. I have another question just crossed my mind. If I am moving fast and I have a mechanical or digital clock, will they TIK TOK more rapidly? If so, Why?
3. ### I Reference for measuring the speed of of light

I don't know what's the appropriate title for my question but here it is: What's the reference we consider to measure the speed with respect to when we say that as the speed of a moving object approaches the speed of light the time becomes slower in the frame of this moving object.
4. ### I Resonant frequency of small particles

Hi How can find the resonant frequency of small objects like dust particles? What factors affect the resonant frequency? And is resonant frequency dependent on size? i.e. if the resonant frequency of 1 cm3 of glass is some certain value, would it be the same for a larger size?
5. ### B Work done by magnetic force

If magnetic force does not exert work on moving charges, how could a current loop immersed in a magnetic field rotate and how could a magnet attract or repel another one?
6. ### I Spooky electrons...

I don't know too much about it. And I think the presenter is trusted and the documentary was broadcast on the BBC. you think this information are wrong?
7. ### I Spooky electrons...

I watched a documentary about Quantum mechanics. There's a phenomenon which Einstien called "spooky action at a distance" states that two electrons appeared in the same event are related to each other in a spooky way,which means that if one of them has a specific state then the other one will...
8. ### Power and frequency

If I have tow sinusoidal voltage sources, one with 50Hz frequency and the other with 60Hz. which one of them will deliver more power if connected to 1 ohm resistor?
9. ### Heater resistor

if I heat a resistor, it will reach a specific temperature and keep it. because as temperature increases the resistance decreases, so reducing the power absorbed. is that true? and how to calculate how much current and voltage I have to deliver to reach a specific temperature?
10. ### A Randomness vs chaos...

The universe is random or chaotic?
11. ### Object oriented programming

Why do we use the interface?
12. ### Object oriented programming

sorry, i want java program
13. ### Object oriented programming

I have a problem with understanding the concepts of "object oriented programming" I do not know what is an instance, object, method,interface... I have read many examples from the real world but I need a sample code with labeled instance, object, method, interface I wish the idea is clear
14. ### Synchronous motor

how is the back emf affected by the flux of the rotor? I know the relation : Ea=k*phi*w but i need a physical explanation
15. ### Transformer efficiency

hello there i have some confusion about transformer efficiency when it is max? and how it is calculated in different loading conditions e.g. at 80% of full load or at given PF
16. ### Power Loss, Current, Resistors, and Voltage

check V=IR again it works
17. ### B Why waves of light don't hit each other?

___________ then, how could photoelectric phenomenon be explained?

exactly
19. ### Power and Resistance

find the equivalent of each parallel combination to reduce the circuit to a single mesh the resultant of (10,5,20) will be less than 5 so it will absorb the least amount of power (90,90)--> 45, the most amount. ______________________________ "parallel circuits take more energy than series" you...
20. ### I Dual nature

Light can act like a wave or a particle ,depending on why? when two photons intersect they must collide since they are particles but rays independence tells they won't
21. ### Kirchoff's Loop Rule Involving 2 Resistors and a Capacitor

R is the parallel combination of R1 and R2
22. ### Kirchoff's Loop Rule Involving 2 Resistors and a Capacitor

Vc(t)=Forced response + Transient response forced response"steady state response" is found at time equals infinity at which the capacitor becomes open circuit here it is : 12*(2/3)=8 volts .... voltage division ____________ transient response (after solving a differential equation) is ...
23. ### Magnetic beakdown

In a ferromagnetic core of a transformer why could breakdown happen if we reach "over_saturation" in other words: magnetic flux could make breakdown in some material just like electric current how does that happen?
24. ### Light speed

well but I have another question about light red things absorb all colors and reflect red green absorb all and reflect green ,and so on why do they do this?
25. ### Light speed

I thought of it in a different way but why? why the does the speed in water is less than it in vaccum?
26. ### Light speed

can someone reduce the speed of light?
27. ### Capacitor and inductors

Physically, can someone explain why does not the voltage on the capcitor change immediatly? and why does not the current in the inductor also do? :smile:
28. ### Complex power

Thx for all ^_^
29. ### Complex power

Why does a load consume reactive power? How can we produce reactive power? And what is the relationship between instantaneous power and complex power?
30. ### Electrostatic charge

someone is my friend and he is studying civil engineering