The speed of a mechanical wave depends on the mechanical properties
of the medium through which the wave is traveling.
The speed of an electromagnetic wave depends on the electrical properties
of the medium through which the wave is traveling.
It's pretty well unanimous for choice <em>A</em> .
Answer:
kinetic and potential energy). The opposite is true when you remove thermal energy: Particles move slower (less kinetic energy). Particles get closer together (less potential energy)
B) 14.0 N
The way to solve this problem is to determine the kinetic energy the box had before and after the rough patch of floor. The equation for kinetic energy is:
E = 0.5 M V^2
where
E = Energy
M = Mass
V = velocity
Substituting the known values, let's calculate the before and after energy.
Before:
E = 0.5 M V^2
E = 0.5 13.5kg (2.25 m/s)^2
E = 6.75 kg 5.0625 m^2/s^2
E = 34.17188 kg*m^2/s^2 = 34.17188 joules
After:
E = 0.5 M V^2
E = 0.5 13.5kg (1.2 m/s)^2
E = 6.75 kg 1.44 m^2/s^2
E = 9.72 kg*m^2/s^2 = 9.72 Joules
So the box lost 34.17188 J - 9.72 J = 24.451875 J of energy over a distance of 1.75 meters. Let's calculate the loss per meter by dividing the loss by the distance.
24.451875 J / 1.75 m = 13.9725 J/m = 13.9725 N
Rounding to 1 decimal place gives 14.0 N which matches option "B".
<span>8,480 Joules. You must multiply by the angle in radians through which the target object rotates. 4.5 x 2 x 3.14 = 28.26666666 J for each turn
28.26666666 x 300 = 8480</span>
Given: Normal pull of gravity g = 9.8 m/s²;
g = 0.855 m/s² (at a certain distance)
Universal gravitational constant G = 6.67 x 10⁻¹¹ N.m²/Kg²
Mass of the Earth Me = 5.98 x 10²⁴ Kg
Radius r = ?
g = GMe/r²
r = √GMe/g
r = √(6.67 x 10⁻¹¹ N.m²/Kg²)(5.98 x 10²⁴ Kg)/(0.855 m/s²)
r = 2.16 x 10⁷ m or
r = 21,610 Km
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