<h2>Work done = mgh </h2>
Explanation:
- In this case, while lifting the book we are working against the force of gravity.
Using the Newton's laws, we can find the force F required for lifting the book having mass (m) and acceleration due to gravity (g) that is ;
and, the change in the position of the book that is Δx (Height)
→ Δx = Final position - Initial position
which is only the height, then the amount of work done will be calculated by :
W= mgh
m = Mass of the Body
g = Acceleration due to Gravity
h = Height of Body being displaced
To test if the hypothesis is correct, a good way is to think of it this way:
Density = mass/volume, right?
Calculate the mass and volume of each and do the equation; this will test your hypothesis.
You will be left with the density of each. But, make sure that the sample sizes are the same (controlled variable) otherwise it will be an unfair test.
First, we convert the depth of the water into meters. This is:
60 feet = 18.3 meters
Now, we compute the additional pressure exerted due to the water, which is given by:
Pressure = density * gravitational field strength * height
P = 1000 * 9.81 * 18.3
P = 179.5 kPa
The atmosphere pressure is 101.325 kPa
The pressure of the gas bubbles 60 feet under water will be:
179.5 + 101.325 = 280.825 kPa
The pressure at the surface of the water will be equal to the atmospheric pressure, 101.325 kPa.
Because of this decrease in external pressure as gas bubbles rise, they are seen to expand.