If dirt and grease were good conductors of electrical current, then we could make wire
out of dirt and grease instead of expensive copper. Sadly, they're not. So a coating of
dirt and grease on the wire can have a substantial impact on the connection, and can
even block the flow of current across the connection completely. Moreover, in the case
where the ends of the wires are to be soldered, solder does not adhere to dirty wire.
Answer:
5.3 m/s
Explanation:
First, find the time it takes for him to fall 7m.
y = y₀ + v₀ t + ½ at²
0 = 7 + (0) t + ½ (-9.8) t²
0 = 7 − 4.9 t²
t ≈ 1.20 s
Now find the velocity he needs to travel 6.3m in that time.
x = x₀ + v₀ t + ½ at²
6.3 = 0 + v₀ (1.20) + ½ (0) (1.20)²
v₀ ≈ 5.27 m/s
Rounded to two significant figures, the man must run with a speed of 5.3 m/s.
Invented the battery
Italian
Has 3 kids
Answer:
$ 0.48
Explanation:
We can calculate this quantity easily using successive products and taking into account the units.
![\frac{0.08}{kw*h}*2[kw]*3[hr]\\ \\=0.48](https://tex.z-dn.net/?f=%5Cfrac%7B0.08%7D%7Bkw%2Ah%7D%2A2%5Bkw%5D%2A3%5Bhr%5D%5C%5C%20%5C%5C%3D0.48)
The amount is $ 0.48
A decrease in it's operating temperature would make a heat engine less efficient. This is because in order to operate, a heat engine needs to be hot and maintain that temperature.
