It's inertia. A rule that you see every day, for example a brick will stay in the same spot unless a force acts on it.
I think shock waves require more speed they travel at the speed of sound
B. Amplitude
It is the maximum distance from the equilibrium point of the pendulum.
The formula that is applicable here is E = kQ/r^2 in which the energy of attraction is proportional to the charges and inversely proportional to the square of the distance. In this case,
kQ1/(r1)^2 = kQ2/(r2)^2 r1=l/3, r2=2l/3solve Q1/Q2
kQ1/(l/3)^2 = kQ2/(2l/3)^2 kQ1/(l^2/9) = kQ2/(4l^2/9)Q1/Q2 = 1/4
C. <span>People need time to shift between two different stimuli.</span>
