Before 1960, it was believed that the maximum attainable coefficient of static friction for an automobile tire was less than 1. then around 1962, three companies independently developed racing tires with coefficients of 1.6. since then, tires have improved, as illustrated in this problem. according to the 1990 guinness book of records, the shortest time interval in which a piston-engine car initially at rest has covered a distance of one- quarter mile is 4.96 s. this record was set by shirley muldowney in september 1989. (a) assume that, as shown in figure p5.3, the rear wheels lifted the front wheels off the pavement. what minimum value of us is necessary to achieve the record time? (b) suppose muldowney were able to double her engine power, keeping other things equal. how would this change affect the elapsed time?

1134567 a jet with mass m = 1.1 ă— 105 kg jet accelerates down the runway for takeoff at 2 m/s2. 1) what is the net horizontal force on the airplane as it accelerates for takeoff? 2.2*10^5 n your submissions: 2.2*10^5 computed value: 220000submitted: saturday, january 26 at 2: 41 pm feedback: correct! 2) what is the net vertical force on the airplane as it accelerates for takeoff? 0 n your submissions: 0 computed value: 0submitted: saturday, january 26 at 2: 41 pm feedback: correct! 3) once off the ground, the plane climbs upward for 20 seconds. during this time, the vertical speed increases from zero to 21 m/s, while the horizontal speed increases from 80 m/s to 95 m/s. what is the net horizontal force on the airplane as it climbs upward? n 4) what is the net vertical force on the airplane as it climbs upward? n 5) after reaching cruising altitude, the plane levels off, keeping the horizontal speed constant, but smoothly reducing the vertical speed to zero, in 13 seconds. what is the net horizontal force on the airplane as it levels off? n 6) what is the net vertical force on the airplane as it levels off?

What happens to an isotope during radioactive decay?

The electric potential a distance r from a small charge is proportional to what power of the distance from the charge? a. r^-1 b. r c. r^-2 d. r^2