Asoccer player runs across a soccer field. a. if the soccer player runs with a speed of 4.6 m/s, how long does it take him to run 60 m? b. it takes the soccer player 3 seconds to reduce his speed to 3.1 m/s. what is his acceleration? c. the soccer player is running at a speed of 4 m/s when he slides on the ground, coming to a stop in a distance of 2 m. what was his acceleration? d. the soccer player accelerates from rest at a rate of 3.1 m/s2. how far does he run in 1.5 seconds? physics

A. speed= distance/ time
s= 4.6m/s
d=60m
4.6= 60/t
4.6t= 60
t= 13.04 seconds

b. acceleration= (the change in velocity/speed)/(time) this is the same as a=Δv/t
a= unkown
Δv= (final speed - initial speed) =  3.1m/s - 4.6m/s=  -1.5m/s
t=3 seconds

a=Δv/t= -1.5/3= -0.5m/s²
the soccer player decelerated by 0.5m/s². This means his speed is decreasing by 0.5m/s². We know it is decreasing because the answer is negative.

c. list given information:
final velocity/speed(FS)= 0m/s
initial velocity/speed(IS)= 4m/s
distance(d)= 2m
time(t)= UNKOWN
acceleration(a)= UNKOWN
(side note: velocity and speed are almost the same thing. The difference between the two words is that velocity usually has a direction and can be negative. Speed cannot be negative. If your problems use the word "speed" I would recommend you continue to use the word "speed" as well. I wanted to clarify this so that you didn't think I was saying to divide velocity by speed.)

Equation: (final speed²)= (inital speed²)+ 2(distance)(acceleration)
FS²=IS²+2da
(0²)= (4²)+ 2(2)a
0=16+4a
-4a=16
a= -4m/s²
The deceleration(decreasing acceleration) is 4m/s². This is because the speed was changing at a rate of negative 4 meters per second squared until reaching a final speed of 0m/s.

d. List given information:
Initial speed: 0m/s (we know he started from "rest" which means his IS was 0) 
Final speed: UNKNOWN 
time= 1.5seconds
distance= UNKOWN
acceleration= 3.1m/s²

Equation: distance= (initial speed * t) + ((1/2)*(acceleration)*(time²)
d= (IS)t + (1/2)at²
d= (0)(1.5)+ (1/2)(3.1)(1.5²)
d= 0 + 3.4785
d≈3.5 meters

Any confusion or questions? Hope this helped!

Iread this book last year so take this with a grain of salt.gene jumps from the tree to compete with finny due to the fact that gene is always trying to do better than finny. he is put under the grasp of peer pressure due to finny almost forcing him to do this. ever since he first jumped finny kept pressuring him to jump since he thought gene enjoyed jumping.rather than uses this answer you should probably just reread chapters 3-4