Answer:
B. 24.2 m/s
Explanation:
Given;
mass of the roller coaster, m = 450 kg
height of the roller coaster, h = 30 m
The maximum potential energy of the roller coaster due to its height is given by;



Therefore, the maximum speed of the roller coaster is 24.2 m/s.
Explanation:
Given that,
Capacitor 
Resistor 
Peak voltage = 5.10 V
(A). We need to calculate the crossover frequency
Using formula of frequency

Where, R = resistor
C = capacitor
Put the value into the formula


(B). We need to calculate the
when 
Using formula of 

Put the value into the formula


(C). We need to calculate the
when 
Using formula of 


(D). We need to calculate the
when 
Using formula of 


Hence, This is the required solution.
Whan object is at equilibrium, then the forces are balanced. Balanced is the key word that is used to describe equilibrium situations.