The refractive index of a transparent material can be determined by measuring the critical angle when the solid is in air. If θc= 40.8° what is the index of refraction of the material?

Which diagram correctly demonstrates the various forces acting on a ball moving horizontally with some speed?

It is really hard for me right know

Apotter's wheel moves uniformly from rest to an angular speed of 0.20 rev/s in 32.0 s. (a) find its angular acceleration in radians per second per second. rad/s2 (b) would doubling the angular acceleration during the given period have doubled final angular speed?