police can estimate the speed of a vehicle before the brakes are applied using the formula 0.75d=s^2/30.25, where s is the speed in miles per hour and d is the length of the vehicle's skid marks. what was the approximate speed of a vehicle that left a skid mark measuring 100 feet?
2007-04-23 10:10:53 · 6 answers · asked by nisha10mabry 3 in Science & Mathematics ➔ Mathematics
0.75d=s^2/30.25
Plug in 100 for d.
0.75(100)=s^2/30.25
75 = s^2 / 30.25
2268.75 = s^2
47.63 = s (approx)
2007-04-23 10:14:55 · answer #1 · answered by Mathematica 7 · 0⤊ 1⤋
To answer this question, we must plug in 100 for d and solve for s, to get the speed of the vehicle.
0.75d=s^2/30.25
0.75(100)=s^2/30.25
75=s^2/30.25
75*30.25=s^2
2268.75=s^2
√(2268.75) = s
Using a calculator, we see that √(2268.75) ≈ 47.63
2007-04-23 10:23:37 · answer #2 · answered by NSurveyor 4 · 0⤊ 0⤋
substituyte d=100ft in
0.75d=s^2/30.25
to get 75 = s^2/30.25 ==> s^2 = 75 x 30.25==> s = sqrt(75 x 30.25)
2007-04-23 10:19:22 · answer #3 · answered by physicist 4 · 1⤊ 0⤋
s^2 = 0.75*d*30.25
s = √[0.75*100*30.25] = 47.6 mph
You did not specify units for d in the equation, so I assumed they were feet (that is the number you gave, and the most likely unit of measurement for skid marks.)
2007-04-23 10:17:42 · answer #4 · answered by gp4rts 7 · 1⤊ 0⤋
0.75d=s^2/30.25
0.75(100)=s^2/30.25
75=s^2/30.25
2268.75=s^2
take the square root of 2268.75 and the approximate speed is 47.631 mps
2007-04-23 10:16:00 · answer #5 · answered by Pluie 2 · 0⤊ 1⤋
the first guy has the right answer
2007-04-23 10:20:38 · answer #6 · answered by Laura 2 · 0⤊ 0⤋