What distance should one speaker be placed behind the other for the sound to have an amplitude 1.80 times that of each speaker alone

The position of a dragonfly that is flying parallel to the ground is given as a function of time by r⃗ =[2.90m+(0.0900m/s2)t2]i^− (0.0150m/s3)t3j^. a: at what value of t does the velocity vector of the insect make an angle of 34.0 degree clockwise from the x-axis? b: at the time calculated in part (a), what is the magnitude of the acceleration vector of the insect? c : at the time calculated in part (a), what is the direction of the acceleration vector of the insect?

Aray of light traveling parallel to the principal axis of a concave mirror will be reflected through the mirror's

Calculate the amount of heat produced when 18000 coulombs of charge is transferred in one hour through a potential difference of 50v