I think you need more information like the force of gravity and the force of the three people. Once you combine the two, however, you should get the net force.
745.92 hz (b)
this is hte answer only because i seen it on the question lol
Answer:
Explanation:
m = Mass attached to spring = 14 kg
g = Acceleration due to gravity = 
x = Displacement of spring = 
k = Spring constant
The force balance of the system is given by
The spring constant for that spring is .
<h2>
Answer:</h2>
Motor
<h2>
Explanation:</h2>
A motor is a machine that converts electrical energy into mechanical energy. In motors, electric energy is converted into mechanic energy when a magnetic torque acts on a conductor that carries a current. There are different types of motors like DC and AC motors. The moving part of a motor is called the rotor while the stationary part is called stator
Recall that
where 
and 
are the initial and final velocities, respecitvely; 
is the acceleration; and 
is the change in position.
So we have
(Normally, this equation has two solutions, but we omit the negative one because the car is moving in one direction.)
