Answer:
a = 0.7267
, acceleration is positive therefore the speed is increasing
Explanation:
The definition of acceleration is
a = dv / dt
they give us the function of speed
v = - (t-1) sin (t² / 2)
a = - sin (t²/2) - (t-1) cos (t²/2) 2t / 2
a = - sin (t²/2) - t (t-1) cos (t²/2)
the acceleration for t = 4 s
a = - sin (4²/2) - 4 (4-1) cos (4²/2)
a = -sin 8 - 12 cos 8
remember that the angles are in radians
a = 0.7267
the problem does not indicate the units, but to be correct they must be m/s²
We see that the acceleration is positive therefore the speed is increasing
Answer:

Explanation:
From the question we are told that:
Acceleration 
Displacement 
Initial time 
Final Time 
Generally the equation for Velocity of 1.05 travel is mathematically given by
Using Newton's Law of Motion



Generally the equation for Distance traveled before stop is mathematically given by



Generally the equation for Distance to stop is mathematically given by
Since For this Final section
Final velocity 
Initial velocity 
Therefore
Using Newton's Law of Motion


Giving

Therefore



Generally the Total Distance Traveled is mathematically given by



Answer:
-22/15
Explanation:
the least common denominator is 15 so first you multiply -2/3 by 5 in both the numerator and denominator making it -10/15
Then you do the same to -4/5 except you multiply the numerator and denominator by 3 giving you -12/15
If you add -10/15+ -12/15 you get -22/15