There are three crates being pushed over a concrete floor by a horizontal force, There are three crates being pushed over a concret, of magnitude 440 N. The masses of the crates are m1=30.0 kg, m2=10.0kg, m3=20.0kg. The coefficient of kinetic friction between the floor and each of the crates is 0.700.

a. What is the magnitude F32 of the force on crate 3 from crate 2?
b. If the crates then slide onto a polished flow, where the coefficient of kinetic friction is less than 0.700, is magnitude F32 more than, less than or the same as it was when the coefficient was 0.700?

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

Aplayground slide is 8.80 ft long and makes an angle of 25.0° with the horizontal. a 63.0-kg child, initially at the top, slides all the way down to the bottom of the slide. (a) choosing the bottom of the slide as the reference configuration, what is the system's potential energy when the child is at the top and at the bottom of the slide? what is the change in potential energy as the child slides from the top to the bottom of the slide? (include the sign of the value in your answer.)

A1.5m wire carries a 2 a current when a potential difference of 52 v is applied. what is the resistance of the wire?