Arectangular key was used in a pulley connected to a line shaft with a power of 7.46 kw at a speed of 1200 rpm. if the shearing stress of the shaft and key are 30 mpa and 240 mpa, respectively what is the length of the rectangular key if the width is one fourth that of the shaft diameter?

The frequency of the fundamental of the guitar string is 320 hz. at what speed v do waves move along that string?

The dipole moment of the water molecule (h2o) is 6.17x10^-30 c.m. consider a water molecule located at the origin whose dipole moment p points in the +x-direction. a chlorine ion ( of charge-1.60x10^-19c , is located at x=3.00x10^-9m . assume that is much larger than the separation d between the charges in the dipole, so that the approximate expression for the electric field along the dipole axis can be used. a) find the magnitude of the electric force that the water molecule exerts on the chlorine ion. b) what is the direction of the electric force. -x-direction or +x-direction c) is this force attractive or repulsive?

which pair of rays would be part of a ray diagram showing reflection? - a & b which pair of rays would be part of a ray diagram showing refraction? c & a