the answer to this qustion is c friction force
Answer:
A. 600 N
Explanation:
the weight of your friend is 60×100=600N
a=Δv/Δt=(v-v₀)/t=(46.1-18.5)/2.47=27.6/2.47=11.17 m/s²
d=v₀t+at²/2=18.5*2.47+11.17*2.47²/2=45.69+34.08=79.776 m
(a)
KE = m v^2 / 2 = (1200 kg)(20 m/s)^2 / 2 = 240,000 J
(b)
The energy is entirely dissipated by the force of friction in the brake system.
(c)
W = delta KE = KEf - KEi = (0 - 240,000) J = -240,000 J
(d)
Fd = delta KE
F = (delta KE) / d = (-240,000 J) / (50 m) = -4800 N
The magnitude of the friction force is 4800 N.
Answer:
as the period decreases, the frequency and energy of the wave increase
Explanation:
Electromagnetic waves are oscillations of the electric and magnetic fields, described by maxwell's equations, the speed of the wave is called the speed of light
c = λ f
E = E cos (kx - wt)
Angular velocity is related to frequency and period.
w = 2π f = 2π / T
Let's analyze what happens when the wave period decreases, angular velocity and frequency increase.
This increase in frequency is reflected with the Planck equation in wave energy
E = h f
Therefore the wave carries more energy and can lead to stronger interactions with matter.
In summary, as the period decreases, the frequency and energy of the wave increase