1- A ranger in a national park is driving at 45 km/h when a deer jumps onto the

Question

1- A ranger in a national park is driving at
45 km/h when a deer jumps onto the road
64 m ahead of the vehicle. After a reaction
time of t s, the ranger applies the brakes to
produce an acceleration of 3.4 m/s2.
What is the maximum reaction time al-
lowed if the ranger is to avoid hitting the
deer?
Answer in units of s.

2- A person travels by car from one city to
another. She drives for 38.2min at 89.3 km/h,
15.9min at 93.7 km/h, 45.5 min at 31.5 km/h,
and spends 10.4 min along the way eating
lunch and buying gas.

a- Determine the distance between the cities
along this route.
Answer in units of km.

b- Determine the average speed for the trip. Answer in units of km/h.

Explanation / Answer

1)Given that velocity is v=45km/h                                        =12.5m/s distance travelled is S=64m deceleration is a=-3.2m/s2 ------------------------------------------ if t is the reaction time then the distance travelled with constant velocity is S1=vt    =12.5t ............... (1) after the application of breaks the distance travelled is S2=- v2/2a    =22.97m so S=S1+S2   S1=S-S2   (12.5t)=64-22.97    t=3.28s hence the  reaction time is t=3.28s   As per cramster there should be only one question per post so please post other question seperately

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