Answer:
displacement at 45 s = 30
65 s = 50
So the average speed over the interval from 45 s to 65 s is
(50 - 30) cm / 20 s = 1 cm / sec
As a check an average speed of 1 cm / sec for 20 sec will produce a
displacement of 1 cm / sec * 20 sec = 20 cm or from 30 to 50 cm
A. freezing, when water turns to ice the water is turning from a liquid to a solid.
Answer:
A volume of a cubic meter of water from the surface of the lake has been compressed in 0.004 cubic meters.
Explanation:
The bulk modulus is represented by the following differential equation:

Where:
- Bulk module, measured in pascals.
- Sample volume, measured in cubic meters.
- Local pressure, measured in pascals.
Now, let suppose that bulk remains constant, so that differential equation can be reduced into a first-order linear non-homogeneous differential equation with separable variables:

This resultant expression is solved by definite integration and algebraic handling:




The final volume is predicted by:

If
,
and
, then:


Change in volume due to increasure on pressure is:



A volume of a cubic meter of water from the surface of the lake has been compressed in 0.004 cubic meters.
Answer:
4.37 * 10^-4 J
Explanation:
Energy stored :
mgΔl / 2
m = mass = 10kg ; g = 9.8m/s² ; r = cross sectional Radius = 1cm = 1 * 10-2 m
Δl = mgl / πr²Y
Y = Youngs modulus = Y=3.5 ×10^10 ; l = Length = 1m
Δl = (10 * 9.8 * 1) / π * (1 * 10^-2)²* 3.5 ×10^10
Δl = 98 / 3.5 * π * 10^6
Δl = 0.00000891267
Energy stored :
mgΔl / 2
(10 * 9.8 * 0.00000891267) / 2
= 0.00043672083 J
4.37 * 10^-4 J
The answer is Strontium(Sr)