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]
Newton's 2nd law of motion:
Force = (mass) x (acceleration)
Divide each side by (mass):
Acceleration = (force) / (mass)
= (100 N) / (50 kg)
= 2 m/s²
Answer:
V=4.7m/s
Explanations:
Let Ma mass of cat A=7kg
Va velocity of cat A=7m/s
Mb mass of cat b=6.1kg
VB velocity of cat b=2m/s
From conservation of linear momentum
MaVa+MbVb=(Ma+Mb)V
7*7+6.1*2=(7+6.1)V
61.2=13.1V
V=4.7m/s
The answer is the fourth choice because there are 7 represents in a coefficient.
I don't know what you mean when you say he "jobs" the other ball, and the answer to this question really depends on that word.
I'm going to say that the second player is holding the second ball, and he just opens his fingers and lets the ball <u><em>drop</em></u>, at the same time and from the same height as the first ball.
Now I'll go ahead and answer the question that I've just invented:
Strange as it may seem, <em>both</em> balls hit the ground at the <em>same time</em> ... the one that's thrown AND the one that's dropped. The horizontal speed of the thrown ball has no effect on its vertical acceleration, so both balls experience the same vertical behavior.
And here's another example of the exact same thing:
Say you shoot a bullet straight out of a horizontal rifle barrel, AND somebody else <em>drops</em> another bullet at exactly the same time, from a point right next to the end of the rifle barrel. I know this is hard to believe, but both of those bullets hit the ground at the same time too, just like the baseballs ... the bullet that's shot out of the rifle and the one that's dropped from the end of the barrel.
