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Question 190778: Can someone please help me with this problem:
A 430-g soccer ball lying on the ground is kicked with a force of 800 N. If the kick lasts 0.01s, the ball flies off with a speed of
a. 0.0186 m/s
b. 0.182 m/s
c. 1.90 m/s
d. 18.6 m/s
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! Note: 430 g = 0.430 kg (the standard mass unit is a kilogram)
First, recall that Newton's Second Law is:
 where "F" is the force applied to the object, "m" is the mass of the object, and "a" is the acceleration that the the object undergoes.
Since "A 430-g soccer ball lying on the ground is kicked with a force of 800 N", this means that  (see note above) and 
So the equation then becomes  and solving for "a" gets us 
So the acceleration is roughly  meters per second squared.
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Now recall that one of the many kinematics equations is
 where "v" is the final velocity,  is the initial velocity, "a" is the acceleration, and "t" is the time the force is applied
So because the initial velocity is 0, this means that  . Since "the kick lasts 0.01s", this means that 
Start with the given kinematics equation.
 Plug in , , and
 Simplify
 Multiply
 Round to the nearest tenth
So the ball flies off at a speed of about 18.6 m/s
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