A dog that goes a maximum speed of 5m/s. It takes 3.0 seconds for the dog to rea

Question

A dog that goes a maximum speed of 5m/s. It takes 3.0 seconds for the dog to reach the maximum speed. The dog is running a race from one end of the room then turns around to come back the track is 20m long. When the dog turns around it loses 0.556 m/s. What is the time the dog finishes the race A dog that goes a maximum speed of 5m/s. It takes 3.0 seconds for the dog to reach the maximum speed. The dog is running a race from one end of the room then turns around to come back the track is 20m long. When the dog turns around it loses 0.556 m/s. What is the time the dog finishes the race

Explanation / Answer

vf = vi + a t

5 = 0 + a(3)

a = 5/3 m/s^2

during first 3 sec:

d = v0 t + a t^2 /2

d1 = 0 + (5/3)(3^2)/2 = 7.5 m

time to decrease by 0.556 m/s

t = 0.556 / (5/3) = 0.037 sec

distance travelled during this time.

5^2 - (5-0.556)^2 = 2(5/3) d2

d2 =1.6 m

distance travelled with constant speed =(20 - 1.6 - 7.5)/5 = 2.18 sec

total time = 2(3 + 2.18 + 0.037) = 10.43 sec  

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.