vf² = vi² + 2ad
vf = vi +at
vf = final velocity
vi = initial velocity
decelerated = a = - (negative)
a. stop ⇒ vf = 0
vf = vi+at
0 = 20 - 1.5t
1.5t=20
t = 13.3 s
b. vi = 20 m/s
0 = 20² - 1.5d
1.5d = 20²
1.5d = 400
d =266.67 m
c. d = vi.t -1/2at²
d = 20.3 - 1/2.1.5.3²
d = 53.25 m
The wavelength in nanometers of light when the energy is 1. 91 × 10^6 j for a mole of photons is <u>62. 8 nm.</u>
Wavelength is the distance among the same points (adjacent crests) within the adjoining cycles of a waveform signal propagated in space or along a cord. In wi-fi structures, this period is typically specified in meters (m), centimeters (cm), or millimeters (mm).
The wavelength is the distance between wave crests, and it is going to be the same for troughs. The frequency is the variety of vibrations that skip over a given spot in one 2nd, and it's far measured in cycles consistent with the second (Hz) (Hertz).
Frequency is the ratio of pace and wavelength in relation to speed. In comparison, wavelength refers to the ratio of pace and frequency. Audible sound waves are characterized by way of a frequency range of 20 to 20 kHz. In contrast, the variety of wavelengths of visible light is from four hundred to seven hundred nm.
<u>calculation:-</u>
*E=hc/λ
1.91 × 10^6 J = (6.62610⁻³⁴) (3.00*10⁸) / λ
λ= (6.62610⁻³⁴) (3.00*10⁸) / 1.91 × 10⁶ J
λ= 1.0410⁻³¹× 10⁻⁹ × 6.022*10²³
=<u> 62. 8 nm </u>
Learn more about wavelength here:-brainly.com/question/10728818
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"Free fall" is the motion of an object when gravity is the ONLY force
acting on it.
In true 'free fall' the speed of an object increases at a constant rate
for the total duration of the fall. The rate of increase, on or near the
Earth's surface, is 9.8 meters per second for each second of fall.
True free fall is almost impossible to observe in everyday life, because
whenever we see anything falling, it's almost always falling through air,
so gravity is NOT the only force acting on it. The friction due to the
motion through air works against the gravitational force. In many cases,
the result is that the object's speed eventually stops increasing and
becomes constant, at a speed often described with the faux technical,
high-fallutin' sounding phrase "terminal velocity". It must be understood
that 'terminal velocity' is NOT a property of gravity or of free fall, but is
only a result of falling through some surrounding stuff that interferes with
the process of true 'free fall'.
Answer:
Phase changes can be reversed