When a jet lands on an aircraft carrier, a hook on the tail of the plane grabs a wire that quickly brings the plane to a halt before it overshoots the deck. In a typical landing, a jet touching down at 240 km/h is stopped in a distance of 95 m .
what is the magnitude of the jets acceleration as it is brought to rest?
how much time does the landing take?

2

Jawapan

2015-12-05T12:56:30+08:00

Ini Jawapan Diperakui

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Jawapan diperakui mengandungi maklumat yang boleh dipercayai dan diharapkan yang dijamin dipilih dengan teliti oleh sepasukan pakar. Brainly mempunyai berjuta-juta jawapan berkualiti tinggi, semuanya disederhanakan dengan teliti oleh ahli komuniti kami yang paling dipercayai, tetapi jawapan diperakui adalah terbaik di kalangan terbaik.
A) You have the initial velocity (240 km/h, or 66.67 m/sec), the final velocity (zero), and the distance (95m), and you want to get the acceleration 
Vfinal^2 = Vinitial^2 + 2ad 
You know Vfinal, Vinitial, d, and you're trying to get a. A little rearranging, and the realization that Vfinal = 0 should get you to 
a = -Vinitial / 2d 
Note, a will be negative, since it's in the direction opposite the initial motion. 
b) Once you finish part a, you now know the acceleration, and the final and initial velocities, and you have: 
Vfinal = Vinitial + a*t 
and since Vfinal is again zero, you end up with 
Vinitial = -a*t t = -Vinitial / a 
remember, a is negative, so even though there are negatives in this equation, it will all make sense. 
Now, a little calculation, and you should get the answers
2015-12-08T12:13:22+08:00

Ini Jawapan Diperakui

×
Jawapan diperakui mengandungi maklumat yang boleh dipercayai dan diharapkan yang dijamin dipilih dengan teliti oleh sepasukan pakar. Brainly mempunyai berjuta-juta jawapan berkualiti tinggi, semuanya disederhanakan dengan teliti oleh ahli komuniti kami yang paling dipercayai, tetapi jawapan diperakui adalah terbaik di kalangan terbaik.
(240/3.6) = 66.67m/sec. 
a) Acceleration = (v^2/2d) = (66.67^2/184) = -24.157m/sec^2. 
b) Time = (v/a) = 66.67/24.157 = 2.76 secs.