boat race starting time
boat race starting time
Help with physics homework?
Been working on my physics homework and there are two I can’t seem to get right. I would appreciate a brief run-through/explanation/whatever of how to do these problems. Thanks for your time.
1.) A race driver has made a pit stop to refuel. After refueling, he leaves the pit area with an acceleration whose magnitude is 6.60 m/s2; after 4.0 s he enters the main speedway. At the same instant, another car on the speedway and traveling at a constant speed of 69 m/s overtakes and passes the entering car. If the entering car maintains its acceleration, how much time is required for it to catch the other car?
2.) A speedboat starts from rest and accelerates at +2.01 m/s2 for 7.50 s. At the end of this time, the boat continues for an additional 6.40 s with an acceleration of +0.518 m/s2. Following this, the boat accelerates at -1.49 m/s2 for 8.70 s. Find the total displacement of the boat.
1) the car leaving the pit reaches the main speedway with a speed of:
v = at = 6.6m/s/s x 4 s = 26.4 m/s
the distance traveled by this car on the speedway is given by:
x=v0t+1/2 at^2 where v0 is the initial speed, a the accel, and t the time of travel (v0 for this car = 26.4, a=6.6)
the other car, traveling at a constant speed, travels a distance of
x=69t
the accelerating car will overtake the constant speed car when:
26.4t+1/2(6.6)t^2=69t
we can divide out a common factor of t to get:
26.4+3.3t=69
t=12.9 secs
2) write the displacement in 3 stages:
x1=1/2 a t^2 = 1/2 (2.01)(7.5)^2
speed at end of this interval, v1=at = 2.01×7.5
x2=v1t +1/2 at^2 = 15.1 (6.4s)+1/2(0.518)(6.4)^2
speed at end of this interval, v2 is v1+at=15.1+(0.518)(6.4)
x3=v2t+1/2 at^2 = v2(8.7s)+1/2(-1.49)(8.7)^2
now all you have to do is chug out the numbers
good luck and hope this helps
Roslagsloppet 2010 Tomta brygga – part 2. Swedish power boat racing.
boat race starting time AMAZON PRODUCTS BELOW
Posted the 26th February 2010 in the category Boat Racing by admin.
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