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.
<h2>
Answer: 1.252</h2>
Explanation:
We are given this equation and we need to find the value of 
:
(1)
Firstly, we have to clear :
(2)
Applying<u> Natural Logarithm</u> on both sides of the equation (2):
(3)
(4)
According to the Natural Logarithm rules 
, so (4) can be written as:
(5)
Finally:
Answer:
real, inverted, and smaller than the object
Explanation:
When the object is placed beyond the center of curvature, the image will formed between the focus and the center of curvature. The size of the image is diminished and its nature is real and inverted.
The whole description is shown in the attached figure. It is clear that the size of the image is smaller than the object.
Answer:
Explanation: nigerian what
