Answer:
Explanation:
In order to solve this problem we need to make a free body diagram of the book and the forces that interact on it. In the picture below you can see the free body diagram with these forces.
The person holding the book is compressing it with his hands, thus exerting a couple of forces of equal magnitude and opposite direction with value F.
Now the key to solving this problem is to analyze the equilibrium condition (Newton's third law) on the x & y axes.
To find the weight of the book we simply multiply the mass of the book by gravity.
W = m*g
W = 1.3[kg] * 9.81[m/s^2]
W = 12.75 [N]
Well depending on the speed of both of those things is were the rock will be placed and it also determines how fast can an environment change
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The formula for kinetic energy is
KE = (1/2) (mass) (speed)² .
How you measure the object's mass and speed is up to you.
You'd need different methods for different objects, and in some
cases, you'd need quite a bit of ingenuity.
Answer:In first case
Explanation:
When two People pull the spring, let the applied force by each person be 
and spring constant of spring be k
so Total force is 
total extension according to Hooke's law is
When they detach the spring and apply force in opposite direction then force on either side is F so net extension is
so in first case there will be more extension
