Tersedia dua bidang miring identik. Bidang pertama permukaan miringnya kasar sedangkan bidang yang kedua permukaan miringnya licin. Dalam percobaan pertama silinder pejal dengan jari – jari R dilepaskan dari puncak bidang miring kasar, sedangkan pada percobaan kedua silinder pejal tersebut dilepaskan dari puncak bidang miring licin. Rasio ( perbandingan ) kelajuan silinder pejal di dasar bidang miring dalam percobaan pertama dan kedua adalah

Answertraveling around a circular trackexplanation"traveling around a circular track" is the best answer as you could be traveling around a circular track at a constant speed. your velocity would therefore have the same magnitude but will always be constantly direction. since acceleration is the rate of change of velocity, the rate of change will only involve the direction of velocity and not the magnitude.wrong choices: "an object at rest" does not accelerate at all"increasing speed while traveling around a curve" means that the acceleration will not be constant due to only change in direction; it will be constant due to both magnitude and direction"an object in free fall" does not necessarily change direction 

An em wave does not require a medium, while a mechanical wave does. 

2/2m is the answer easy