#Case -1
If Pulling force is less than frictional force the object won't move .
#Case-2
If Pulling force is greater than frictional force then object will be .
In order to calculate friction force you need Limiting friction first .

u s is coefficient of static friction and N is normal reaction
Or

<u>Answer</u>
Part 1) Increase
Part 2) expand
Part 3) rise
<u>Explanation</u>
When the air is heated the molecules gain kinetic energy and starts to collide with walls of the ballon making it to increase it size.
Thus the volume of the balloon expands. When this happens the balloon and its content becomes less dense and it rises.
After one half-life, 8 g of radioactive isotope will remain in the sample.
<h3>What is radioactivity?</h3>
The act of producing radiation spontaneously is known as radioactivity. This is accomplished by an unstable atomic nucleus that want to give up some energy in order to move to a more stable form.
The following formula is used to compute the number of half lives elapsed:

Hence,8 gram of radioactive isotope remains in the sample after 1 half-life.
To learn more about the radioactivity, refer to the link;
brainly.com/question/1770619
#SPJ1
Answer:
0.11m
Explanation:
let's assume the boat is of uniform construction
Ignoring friction losses
Also assume the origin is at the end of the boat originally with the heavier person
the center of mass of the whole system will not change relative to the water when the two swap ends
Originally, the center of mass is
85[0] + 90[3.5/2] + 50[3.5] / (85 + 90 + 50) = 1.14m from the origin
after the swap, the center of mass is
50[0] + 90[3.5/2] + 85[3.5] / (85 + 90+ 50) = 1.030m from the origin
The center of mass has shifted
1.14-1.030 = 0.11m
as no external force acted on the system, the center of mass relative to the water will not change. The boat will therefore shift towards the end where the heavier person originally sat
Answer:
Increasing until terminal velocity is reached
Explanation:
Provided the scream is a constant pitch at the source, Doppler effect will make the pitch increase as the velocity of the source towards the listener increases.