Newtons' First Law

A body will remain stationary or movig in a straight line at a constant speed as long as the forces acting upon it are balanced. 

Stationary Bodies

The Forces acting on a stationary object are balanced: Weight- 25N

                                                                                        Tension- 25N

Bodies moving at a constant speed

The Forces acting upon a body moving at a constant speed/rate, and moving in a straight line, are balanced: Reaction Force- 15kN

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