Answer:
(a)10.5 rad/s2
(b) 20.9 rev
(c) 47.27 m
Explanation:
As the block of mass 53 kg is falling and pulling on the rope. The tension force on the rope must be equal to the gravity acting on the block according to Newton's 3rd law
T = mg = 53*9.81 = 519.93 N
Since this tension force would rotate the cylinder freely without any friction. The torque created by this tension force is
To = TR = 519.93 * 0.36 = 187.17 Nm
This solid cylinder would have a moment of inertia around it's rotating axis of:

(a)We can use Newton's 2nd law to calculate the angular acceleration exerted by such torque on the solid cylinder

(b) With such constant angular acceleration, the angle it would make after 5s is

Since each revolution equals to
of angle, we can calculate the number of revolution it makes

(c) Assume the thickness of the rope is negligible (and its wounded radius is unchanging), we can calculate the rope length unwinded after rotating 131.3rad

Salt water offers the least electrical resistance.
<u>Explanation:</u>
Least electrical resistance indicates that any material which readily allows the electric current through itself, and shows more conductivity.
Here pure water doesn't contain any ions, so it is a bad conductor.
Wood and glass are also bad conductors of electricity.
Salt water contains ions, which conducts electricity which means it shows least electrical resistance.
... low frequency and high amplitude.
Answer:
Explanation:
Total distance covered = 25 + 15 = 40 m
Total time = 15 + 8 = 23 s
Average speed = total distance covered / total time
= 40 / 23
= 1.74 m / s
Total displacement = 25 - 15 = 10 m
Total time = 15 + 8 = 23 s
Average velocity = total displacement / total time
= 10 / 23
= .434 m / s to the right .