Answer:
0.76 oscillations per second
Explanation:
Time period = [tex]2\pi \sqrt{m/k}[/tex] where k is the spring constant and m is the mass attached to the spring.
Calculating the spring constant:
1/1.5=[tex]2\pi\sqrt{1300/k}[/tex];
k=3.68*10^4
When the car is loaded, its mass increases to 1300+ 4*78 = 1612
Calculating the new time period:
T=[tex]2\pi \sqrt{1612/36800}[/tex]=1.1315s
Frequency=1/T;
