Answer:
I think it's because it's an insulator and like charges attract
The major reason why a wet saw that is used in cutting optical crystals is constantly lubricated with oil is largely due to friction, lubrication decreases friction and minimises the increase of internal energy.
Friction is basically the coming together of two parts that rubs against each other, it causes heat and lead to deterioration of surfaces, it can also lead to wear and tear.
Although, despite it down side, friction is desire-able in most applications
e.g the brake system of vehicles, and if not for friction, we humans cannot walk without falling
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brainly.com/question/24338873
Answer:
A charged battery that is NOT part of a circuit is an example of potential energy.
Answer:
a. 1222.13 J b. 2.36 m. His new position is above his original position
Explanation:
From work-kinetic energy principle, workdone = change in kinetic energy
So work the skateboarder does on himself W₁ = -116 J
work done by friction W₂ = -264 J
gravitational potential energy change W₃ = mgΔy
The kinetic energy change ΔK = 1/2m(v² - u²) where m = mass of skater = 52.9 kg, u = initial speed of skaterboarder = 2.04 m/s and v = final speed of skaterboarder = 6 m/s. ΔK = 1/2m(v² - u²) = ΔK = 1/2 × 52.9(6² - 2.4²) = 842.13 J
So, W₁ + W₂ + W₃ = ΔK
W₃ = ΔK - W₁ - W₂ = 842.13 J - (-116 J) - (-264J) = 842.13 J + 116 J + 264J = 1222.13 J
b. Since W₃ = mgΔy = 1222.13 J
Δy = W₃/mg = 1222.13/(52.9 × 9.8) = 1222.13/518.42 = 2.36 m
Since Δy > 0, his new position is above his original position.
Use this equation
Distance(s)=speed(v)•time(t)
Given,req-soln
1.
S=10cm=0.1m
t=4sec
V=s/t=>0.1•10/4•10=>1/40=0.025
2.
V=0.1m/s
t=1.5 sec
S=vt =0.1•1.5=0.15
