a. The speed of the pendulum when it reaches the bottom is 0.9 m/s.
b. The height reached by the pendulum is 0.038 m.
c. When the pendulum no longer swing at all, all the kinetic energy of the pendulum has been used to overcome frictional force.
<h3>Kinetic energy of the pendulum when it reaches bottom</h3>
K.E = 100%P.E - 18%P.E
where;
K.E(bottom) = 0.82P.E
K.E(bottom) = 0.82(mgh)
K.E(bottom) = 0.82(1 x 9.8 x 0.05) = 0.402 J
<h3>Speed of the pendulum</h3>
K.E = ¹/₂mv²
2K.E = mv²
v² = (2K.E)/m
v² = (2 x 0.402)/1
v² = 0.804
v = √0.804
v = 0.9 m/s
<h3>Final potential energy </h3>
P.E = 100%K.E - 7%K.E
P.E = 93%K.E
P.E = 0.93(0.402 J)
P.E = 0.374 J
<h3>Height reached by the pendulum</h3>
P.E = mgh
h = P.E/mg
h = (0.374)/(1 x 9.8)
h = 0.038 m
<h3>when the pendulum stops</h3>
When the pendulum no longer swing at all, all the kinetic energy of the pendulum has been used to overcome frictional force.
Thus, the speed of the pendulum when it reaches the bottom is 0.9 m/s.
The height reached by the pendulum is 0.038 m.
When the pendulum no longer swing at all, all the kinetic energy of the pendulum has been used to overcome frictional force.
Learn more about pendulum here: brainly.com/question/26449711
#SPJ1