A disk of a radius 50 cm rotates at a constant rate of 100 rpm. What distance in meters will a point on the outside rim travel during 30 seconds of rotation? ​ ​

157 m

Explanation:

30 s = ½ min, so 100 / 2 = 50 revolutions

d = rθ = 0.50(50(2π)) = 50π m = 157 m

answer: he got 23

explanation:

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )