The third choice is correct
Answer:
40sec
Explanation:
Data
Work = 440 J
Power= 11watt
time = ?
Power = work done/time
===> time = work done/power
= 440/11
= 40sec
Answer:
Red light
Explanation:
The energy emitted during an electron transition in an atom of hydrogen is given by

where
is the energy of the lowest level
n1 and n2 are the numbers corresponding to the two levels
Here we have
n1 = 3
n2 = 2
So the energy of the emitted photon is

Converting into Joules,

And now we can find the wavelength of the emitted photon by using the equation

where h is the Planck constant and c is the speed of light. Solving for
,

And this wavelength corresponds to red light.
Answer:
1.7323
Explanation:
To develop this problem, it is necessary to apply the concepts related to refractive indices and Snell's law.
From the data given we have to:



Where n means the index of refraction.
We need to calculate the index of refraction of the liquid, then applying Snell's law we have:



Replacing the values we have:


Therefore the refractive index for the liquid is 1.7323