When car is at rest the steaks makes makes vertical lines
which means the rain is falling in vertically downward direction
Now when car is moving with some speed v
Now the steaks makes and an angle 45 degree
So here we can say that relative velocity of rain with car is 45 degree
Now this is the resultant speed of rain in car frame

now if relative velocity makes 45 degree angle so this vector must have same components in vertical and horizontal direction
Since we know that relative velocity is resultant of rain velocity and car velocity so we can say here its two components are rain velocity and car velocity
So these two components must be of same magnitude
as it makes 45 degree
because when two vector are of same magnitude then the resultant vector always makes 45 degree with them if these two vectors are perpendicular to each other
car is moving at same speed as the speed of rain
(a) The system of interest if the acceleration of the child in the wagon is to be calculated are the wagon and the children outside the wagon.
(b) The acceleration of the child-wagon system is 0.33 m/s².
(c) Acceleration of the child-wagon system is zero when the frictional force is 21 N.
<h3>
Net force on the third child</h3>
Apply Newton's second law of motion;
∑F = ma
where;
- ∑F is net force
- m is mass of the third child
- a is acceleration of the third child
∑F = 96 N - 75 N - 12 N = 9 N
Thus, the system of interest if the acceleration of the child in the wagon is to be calculated are;
- the wagon
- the children outside the wagon
<h3>Free body diagram</h3>
→ → Ф ←
1st child friction wagon 2nd child
<h3>Acceleration of the child and wagon system</h3>
a = ∑F/m
a = 9 N / 27 kg
a = 0.33 m/s²
<h3>When the frictional force is 21 N</h3>
∑F = 96 N - 75 N - 21 N = 0 N
a = ∑F/m
a = 0/27 kg
a = 0 m/s²
Learn more about net force here: brainly.com/question/14361879
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<span>The correct frequency when you tune a guitar is
when you hear the right tune in your own hearing and standard. The measure
frequency of a guitar string is when you measure the tune of the string
correctly. This is not the same because manual tuning is affected by many
factors.</span>
Answer:
Explanation:
60000 kJ / h = 60000 x 1000 / (60 x 60 )
= 16667 J /s
a)

where
and
are heat supplied and heat given from outside source .
Here
= 16667 J/s

= 15.684

16667 / W = 15.684
W= minimum power supplied = 1062.7 W.
b )
If 

=19.87



= 838.8 W .
Answer: Option (b) is the correct answer.
Explanation:
As on increasing the temperature, the molecules gain more kinetic energy due to which they tend to collide and move rapidly from one place to another.
Thus, we can conclude that when temperature is increased, the kinetic energy of the molecules increases. This means that temperature is directly proportional to the average kinetic energy of a gas.