Mechanical energy (ME) is the sum of potential energy (PE) and kinetic energy (KE). When the toy falls, energy is converted from PE to KE, but by conservation of energy, ME (and therefore PE+KE) will remain the same.
Therefore, ME at 0.500 m is the same as ME at 0.830 m (the starting point). It's easier to calculate ME at the starting point because its just PE we need to worry about (but if we wanted to we could calculate the instantaneous PE and KE at 0.500 m too and add them to get the same answer).
At the start:
ME = PE = mgh
ME = 0.900 (9.8) (0.830)
ME = 7.32 J
        
             
        
        
        
143m/s if you just perhaps by what you know you'll figure it out
        
             
        
        
        
The force must be applied for motor to keep the package moving is 50 N.
<h3>What is force?</h3>
Force is the action of push or pull the object in order to make it move or stop.
Power is related to force and velocity as
P = F x v
150 W = F x 3 m/s
F  =50 N
Thus, the force must be applied for motor to keep the package moving is 50 N.
Learn more about force.
brainly.com/question/13191643
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A region within a magnetic material in which magnetization is in a uniform direction this means the individual magnetic moments of the atoms are aligned with one another and they point the same direction. when cooled bwlow a temperature called the curie temperature the magnetization of a piece of ferromagnetic material.<span />