The main requirement for a good conductor of electricity is to have a lot of valence electrons. Valence electrons are the electrons of the outer shells of atoms not bound with other atoms (for example through covalent bounds). These electrons are "free to escape" as soon as an electric field with enough intensity is applied to the material, and therefore these electrons will be free to move in the material producing an electric current.
The change in Potential energy of the cat is 176.4 J.
<h3 /><h3>Potential Energy:</h3>
This is the energy due to the position of a body. The S.I unit is Joules (J)
The formula for change in potential energy.
<h3 /><h3>Formula:</h3>
- ΔP.E = mg(H-h).............. Equation 1
<h3>Where:</h3>
- ΔP.E = Change in potential energy
- m = mass of the cat
- g = acceleration due to gravity
- H = First height
- h = second height.
From the question,
<h3>Given:</h3>
- m = 15 kg
- H = 2.5 m
- h = 1.3 m
- g = 9.8 m/s²
Substitute these values into equation 1
- ΔP.E = 15×9.8(2.5-1.3)
- ΔP.E = 15×9.8×1.2
- ΔP.E = 176.4 J.
Hence, The change in Potential energy of the cat is 176.4 J
Learn more about Potential energy here: brainly.com/question/1242059
Answer: h = 3.34 m
Explanation:
If the hat is thrown straight up, then at its highest point it has no motion and no kinetic energy. All energy is potential energy
PE = mgh
h = PE/mg = 4.92 / (0.150(9.81)) = 3.34352... ≈3.34 m
The angle of inclination is calculated using sin
function,
sin θ = 5 m / 20 m = 0.25
θ = 14.4775°
<span>The net force exerted is then calculated:
F net = m g sin θ = 20 * 9.8 * 0.25 </span>
F net = 49N
<span>Work is product of net force and distance:
W = F net * d = 49 * 20 </span>
<span>Work = 980 J </span>
Heat engines are less than 100% efficient because absolute zero cannot be reached