The answer to the question above is "630.25 hours" which is the time to recoup the difference in the water heater cost. This problem can be solved using a simple algebra equation which stated as (18*115*0.1/1000)x - (4*220*0.1/1000)x = $75. In this formula, x represents the time to recoup the difference in the water heater cost (Calculation: 0.207x-0.088x=75 --> 0.119x = 75 --> x = 630.25)<span>. </span>
Answer:
Part a)

Part b)

Explanation:
As the uniform sphere is rolling down the inclined plane then the net force on the sphere is given as

also we have torque equation on it

for pure rolling


now we have

now we have


now given that

so we have



Part b)
If the inclined plane is frictionless then the acceleration is given as



Answer:
a) 
b) 
Explanation:
Given:
height of water in one arm of the u-tube, 
a)
Gauge pressure at the water-mercury interface,:

we've the density of the water 


b)
Now the same pressure is balanced by the mercury column in the other arm of the tube:



<u>Now the difference in the column is :</u>



Answer:
Explanation:
Given
Distance = 4.0m
Time = 5.0 mins = 300secs
Required
Average speed
Average speed = Distance/Time
Average speed = 4.0/300
Average speed = 0.01333m/secs
Hence the average speed of the snail is 0.01333m/s