<span>Answer: Force = 81.6 N
Explanation:
According to Newton's Second law:
F = ma --- (1)
Where F = Force = ?
m = Mass = 68 kg
a = Acceleration = 1.2 m/s^2
Plug in the values in (1):
(1) => F = 68 * 1.2
F = 81.6 N (The force needed to accelerate the skier at a rate of 1.2 m/s^2)</span>
If it starts at rest the initial velocity is 0.
For an acceleration, a, and time, t, the velocity is v=at. Since at t=4, v=7, then a=7/4=1.75m/s^2
Explanation:
An perfect mass less spring, attached at one end and with a free mass attached at the other end, will have a distinct frequency of oscillation depending on its constant spring and mass. On the other hand, a spring with mass along its length will not have a characteristic frequency of oscillation.
Alternatively, based on its spring constant and mass per length, it will now have a wave Speed. It would be possible to use all wavelengths and frequencies, as long as the component fλ= S, where S is the spring wave size. If that sounds like longitudinal waves, like solid sound waves.
Answer:
ΔE = 1.031 eV
Explanation:
For this exercise let's calculate the energy of the photons using Planck's equation
E = h f
wavelength and frequency are related
c = λ f
f = c /λ
let's substitute
E = h c /λ
let's calculate
E = 6.63 10⁻³⁴ 3 10⁸/1064 10⁻⁹
E = 1.869 10⁻¹⁹ J
let's reduce to eV
E = 1.869 10⁻¹⁹ J (1 eV / 1.6 10⁻¹⁹ J)
E = 1.168 eV
therefore the electron affinity is
ΔE = E - 0.137
ΔE = 1.168 - 0.137
ΔE = 1.031 eV
