Answer:
50 N
Explanation:
Since the refrigerator doesn’t move, that means the force of friction equals the amount of force the child exerts on the fridge. If the friction force were greater than the force by the child, the fridge would start accelerating towards the child. If it were less than the force the child exerted, the fridge would start accelerating away from the child. Therefore, the net force must be 0, in this case, the friction force is equal to the force the child exerted, for it to stay at rest (as Newton’s First Law stated). 
I hope this helps! :)
 
        
             
        
        
        
Explanation:
Only few supernova are observed in our galaxy -
Type II supernovae ( i.e. the explosions of the massive stars ) occurred in the Milky Way, and they might be hidden by the intervening dust if they are located in the more distant parts of our Galaxy .
Type Ia supernovae , which need a white dwarf star in the binary star system , are brighter than the type II supernovae , but some of them could also happen in the older parts of Galaxy which are hidden due to the buildup of the dust and gas .
 
        
             
        
        
        
Answer:
The wavelength of the light is  .
.
Explanation:
Given that,
Distance between the slit centers d= 1.2 mm
Distance between constructive fringes 
Distance between fringe and screen D= 5 m
We need to calculate the wavelength 
Using formula of width

Put the value into the formula




Hence, The wavelength of the light is  .
.
 
        
             
        
        
        
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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