The position-time graphs show the relationship between the position of an object (shown on the y-axis) and the time (shown on the x-axis) to show velocity.
<h3>What is velocity?</h3>
Velocity is a vector quantity that tells the distance an object has traveled over a period of time.
Displacement is a vector quality showing total length of an area traveled by a particular object.
Imagine a time-position graph where the velocity of an object is constant. What will be observed on the graph concerning the slope of the line segment as well as the velocity of the object?
The slope of the line is equal to zero and the object will be stationary.
The position-time graphs show the relationship between the position of an object (shown on the y-axis) and the time (shown on the x-axis) to show velocity.
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As temperature decreases, the steel will contract (volume decreases) thereby, an increase in Density.
The weight of a column of air with cross-sectional area 4. 5 m^2 extending from earth's surface to the top of the atmosphere is, 4.56*10^5N.
To find the answer, we have to know about the pressure.
<h3>How to find the weight of a column of air?</h3>
- As we know that the expression of pressure as,

where; F is the force, here it is equal to the weight of the air column, and A is the area of cross section.
- It is given that, the air column is extending from earth's surface to the top of the atmosphere, thus, the pressure will be atmospheric pressure,

- From this, the value of weight will be,

Thus, we can conclude that, the weight of a column of air with cross-sectional area 4. 5 m^2 extending from earth's surface to the top of the atmosphere is, 4.56*10^5N.
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Answer:
0.196 m
Explanation:
Given in the question that,
time taken by the dolphin to go back to water = 0.2 sec
To solve the question we will use Newton's Law of motion
<h3>S = ut + 0.5(a)t²</h3>
here S is distance covered
u is initial speed
a = acceleration due to gravity
t = time taken
Plug value in the equation above
S = 0(0.2) + 0.5(-9.8)(0.2)²
S = 0.5(-9.8)(0.2)²
S = -0.196 m
Negative sign represent direction
(Assuming that dolphin have a vertical straight jump not a projectile motion)
If the friction increase it would make the thing sliding down slower and makes heat