Answer:
The power for circular shaft is 7.315 hp and tubular shaft is 6.667 hp
Explanation:
<u>Polar moment of Inertia</u>

= 0.14374 in 4
<u>Maximum sustainable torque on the solid circular shaft</u>

=
= 3658.836 lb.in
=
lb.ft
= 304.9 lb.ft
<u>Maximum sustainable torque on the tubular shaft</u>

= 
= 3334.8 lb.in
=
lb.ft
= 277.9 lb.ft
<u>Maximum sustainable power in the solid circular shaft</u>

= 
= 4023.061 lb. ft/s
=
hp
= 7.315 hp
<u>Maximum sustainable power in the tubular shaft</u>

= 
= 3666.804 lb.ft /s
=
hp
= 6.667 hp
To solve this problem we will use the concepts related to Magnification. Magnification is the process of enlarging the apparent size, not physical size, of something. This enlargement is quantified by a calculated number also called "magnification".
The overall magnification of microscope is

Where
N = Near point
l = distance between the object lens and eye lens
= Focal length
= Focal of eyepiece
Given that the minimum distance at which the eye is able to focus is about 25cm we have that N = 25cm
Replacing,


Therefore the correct answer is C.
Explanation :
The forces acting on hot- air balloon are:
Weight, (W)
Force due to air resistance, (F)
Upthrust force, (U)
Its weight W is acting in downward direction. The upthrust force U acts in upward direction. When the balloon is moving upward, the air resistance is in downward and vice versa.
In this case, the hot-air balloon descends vertically at constant speed.
so, 
and 
so,
....................(1)
when it is ascending let the weight that it is releasing is R, so
..........(2)
solving equation (1) and (2)

2F is the weight of material that must be released from the balloon so that it ascends vertically at the same constant speed.
Electrons move from the atoms in the cloth to the atoms in the balloon, causing the balloon to have a negative charge
Hope this helps!!!
Answer:
The objects must be different temperatures.
Explanation:
For heat to flow between two objects, heat must be flowing between them. The thermal gradient allows for the flow of heat. Heat is a form of energy that is dissipated from one place to another based on temperature difference.
Temperature is the degree of hotness or coldness of body. It is power by heat energy between two bodies.
Heat generally flows from a body at high temperature to one at low temperature. When thermal equilibrium is established and both bodies have the same temperature, heat will stop to flow.