Answer:
correct answer is C
Explanation:
The photoelectric effect was correctly described by Einstein, where he assumes that the light ray is formed by photons that are articulated and behaves like an elastic shock, the energy of this particular is described by the Planck equation.
K = h f + Ф
where k is the kinetic energy of the electrons, f the frequency of the photons and Ф the work function of the material.
In this experiment, red light removes electrons, it is assumed that each photon spreads an electron if we have another light with more energy and 10% more intense, that is, with 10% more shapes and each arcane an electron the number of electrons removed of; material is increased by 10%.
The change in wavelength and consequently the frequency
c = λ f
f = c /λ
therefore, the wavelength of the voilet λ = 400 num has a higher frequency and therefore more energy, so that the turned-on turns have more kinetic energy.
With these approaches we examine the final answers where the correct answer is C
Answer: If there is a higher friction, the opposition force is higher so that it can reduce our speed. So, a factor that affects friction is the roughness or smoothness of the surface of the object. In comparison of the table with the fabric, the fabric will have a more opposition force. As the surface of the fabric is usually rougher than the surface of a smooth table. As there is more friction on a fabric, we will feel more opposition force on our finger tip.
Hope it helped! :>
Answer:
(a) Vf = 128 ft/s
(b) K.E = 122.8 Btu
Explanation:
(a)
In order to find the velocity of the object just before striking the surface of earth or the final velocity, we use 3rd equation of motion:
2gh = Vf² - Vi²
where,
g = 32.2 ft/s²
h = height = 253 ft
Vf = Final Velocity = ?
Vi = Initial Velocity = 10 ft/s
Therefore,
(2)(32.2 ft/s²)(253 ft) = Vf² - (10 ft/s)²
16293.2 ft²/s² + 100 ft²/s² = Vf²
Vf = √(16393.2 ft²/s²)
<u>Vf = 128 ft/s</u>
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(b)
The kinetic energy of the object before it hits the surface of earth is given by:
K.E = (0.5)(m)(Vf)²
where,
m = mass of object = 375 lb
K.E = Kinetic energy of object before it strikes the surface of earth = ?
Therefore,
K.E = (0.5)(375 lb)(128 ft/s)²
K.E = 3073725 lb.ft²/s²
Now, converting this to Btu:
K.E = (3073725 lb.ft²/s²)(1 Btu/25037 lb.ft²/s²)
<u>K.E = 122.8 Btu</u>
The right answer to this question is A. a crest that is toppling over. When a surfer rides an ocean wave on her surfboard, she is actually riding on a crest. The crest is the point on a wave with the maximum value or upward displacement within a cycle.
Answer:
Its simple! B The ball accelerates upward!♡♡