Answer:
Explanation:
Look at the equation for Potential Energy. PE = mass times gravity times the height. Filling in and solving for h:
34.3 = .5(9.8)h so
34.3 = 4.9h so
h = 7 meters
The correct answer is option A, 3.528 N
In this question the water has nothing to do, the gravity always pull the object with the same magnitude irrespective of the medium.
The force of gravity is calculated as
F=0.09*4000*9.8
=3.528 N
Answer:
(a) 8.362 rad/sec
(b) 6.815 m/sec
(c) 9.446 
(d) 396.22 revolution
Explanation:
We have given that diameter d = 1.63 m
So radius 
Angular speed N = 79.9 rev/min
(a) We know that angular speed in radian per sec

(b) We know that linear speed is given by

(c) We have given final angular velocity 
And 
Time t = 63 sec
Angular acceleration is given by 
(d) Change in angle is given by

The answer is negative three
Answer:
B) Periodic Motion
Explanation:
When a pendulum is friction-less, i.e there are no damping forces acting on it, its motion will be periodic, i.e it will bob up and down going from potential energy to kinetic energy and back. Thus, the motion of the pendulum can be best described by the term "period motion", hence choice B.
If however, forces do act on the pendulum, and if they acts as to damp the pendulum, it will oscillate less and less as time goes by, and eventually come to a stop (in the real world this damping force is usually air resistance ). And if the force acts in such a way that it increases the oscillations, the pendulum will swing higher and higher, and the system will go haywire! :)