You are driving at the speed of 33.4 m/s (74.7296 mph) when suddenly the car in front of you (previously traveling at the same speed) brakes. considering an average human reaction, you press your brakes 0.424 s later. assume that the brakes on both cars are fully engaged and that the coefficient of friction is 0.862 between both cars and the road.
the acceleration of gravity is 9.8 m/s2 .
a) calculate the acceleration of the car in front of you when it brakes.
b) calculate the braking distance for the car in front of you.
c) find the minimum safe distance at which you can follow the car in front of you and avoid hitting it (in the case of emergency braking described here).

In the future, people will only enjoy one sport: electrodisc. in this sport, you gain points when you cause metallic discs hovering on a field to exchange charge. you are an electrodisc player playing the popular four disc variant. the disks have charges of qa = −8.0 µc, qb = −2.0 µc, qc = +5.0 µc, and qd = +12.0 µc. (1) you bring two disks together and then separate them. you measure the resulting charge of these two disks and find that it is +5.0 µc per disk. which two disks did you bring together? (a) a and b (b) a and c (c)a and d (d)b and c(e) b and d (f) c and d. (2) you bring three disks together and then separate them. you measure the resulting charge of these three disks and find that it is +3.0 µc per disk. which three disks did you bring together? a, b, and c (a) a, b, and d (c) a, c, and d (d) b, c, and d. (3) given the resulting charge of each disk measured in (b) is +3.0 µc, how many electrons would you need to add to a disk of this charge to electrically neutralize it? electrons