Answer:
Violet has a higher frequency (approximately 7.5×1014 Hz 7.5 × 10 14 Hz ) than red light (approximately 4.3×1014 Hz 4.3 × 10 14 Hz ). Since the speed of both waves is the same, we infer that violet has a shorter wavelength (400 nm ) than red (700 nm ).
Explanation:
hope it helps this took a lot of my time please mark brainlets!
Answer:
Here ball and rod will repel each other as they are of similar charges
Explanation:
As we know that the two charges attract or repel each other by electrostatic force
This force is given as

so we know if two charges are similar in nature then they will repel each other and if the two charges are opposite in nature then they will attract each other
So here when rod touch the ball then it transfer its charge to the ball and due to similar charges in ball and rod they both repel each other
Answer:
9V
Explanation:
The potential difference across the terminal as the same and thats because we are assuming that the source has no internal resistance.
Internal resistance are usually little resistances in the supply.
The proof that the earth is rotating is the happens of night and day also the seasons, eg. winter, summer, autumn.
Answer: a) 274.34 nm; b) 1.74 eV c) 1.74 V
Explanation: In order to solve this problem we have to consider the energy balance for the photoelectric effect on tungsten:
h*ν = Ek+W ; where h is the Planck constant, ek the kinetic energy of electrons and W the work funcion of the metal catode.
In order to calculate the cutoff wavelength we have to consider that Ek=0
in this case h*ν=W
(h*c)/λ=4.52 eV
λ= (h*c)/4.52 eV
λ= (1240 eV*nm)/(4.52 eV)=274.34 nm
From this h*ν = Ek+W; we can calculate the kinetic energy for a radiation wavelength of 198 nm
then we have
(h*c)/(λ)-W= Ek
Ek=(1240 eV*nm)/(198 nm)-4.52 eV=1.74 eV
Finally, if we want to stop these electrons we have to applied a stop potental equal to 1.74 V . At this potential the photo-current drop to zero. This potential is lower to the catode, so this acts to slow down the ejected electrons from the catode.