The uniform 37-lb bar with attached 14-lb wheels is released from rest when θ = 60°. If the wheels roll without slipping on the horizontal and vertical surfaces, determine the magnitude of the angular velocity of the bar when θ = 32°. Each wheel has a centroidal radius of gyration of 7.1 inches.

The rearrangement of particles in a physical change. hope this

Initial velocity,  u = 4.9 m/sfinal velocity = v m/sinitial height,  h₁ =  245 m    final height, h₂ = 0a = -9.8  m/s²time taken = t secondss = ut + 0.5at²⇒  (h₂-h₁) = ut + 0.5at²⇒  0-245 = 4.9t + 0.5×(-9.8)×t²⇒ -245 = 4.9t - 4.9t²⇒ 4.9t² -4.9t -245 =0solving it, we get   t = 7.59sv  = u +  at = 4.9 -9.8×7.59 = 4.9 - 74.38 = -69.48 m/svelocity is  69.48 m/s downward

Planck decided to assume that atoms could only vibrate at certain frequencies that were whole numbers eg 2f, 3f and so on. others used to think that atoms vibrate continuously