Answer:
B Negative
Explanation:
Its negative because when your going 25 mph your moving faster and when your coming up to the stop sign you will start to slow down going 10 mph then 0 mph when you reach the stop sign so it will be negative.
k = spring constant of the spring = 100 N/m
m = mass hanging from the spring = 0.71 kg
T = Time period of the spring's motion = ?
Time period of the oscillations of the mass hanging is given as
T = (2π) √(m/k)
inserting the values in the above equation
T = (2 x 3.14) √(0.71 kg/100 N/m)
T = (6.28) √(0.0071 sec²)
T = (6.28) (0.084) sec
T = 0.53 sec
hence the correct choice is D) 0.53
Finding acceleration= final speed-initial speed/time taken (or A=V-U\T)
Finial speed= 27.8s
Initial speed= 0s
Time taken= 5.15
So..
27.8-0/5.15= 5.40m/s (rounded to two decimal places)