An imbalance of electrons causes an object to be charged. A charged substance is one that has a net charge that is not zero. If the number of protons and that of electrons is equal in an object, the object is not neutral, but it has zero charge. Loss or gain of electrons determine the charge of an object, when an object loses electrons it becomes positively charged, but when it gains electrons it becomes negatively charged.
Really? wow that's pretty cool
Answer:
The lightbulb will NOT light.
Explanation:
You put me in a difficult position. I can't help it, but the "sample answer" is by far the best way to explain this, briefly and correctly. There's no other choice but to copy it.
This is a short circuit. The branch without the bulb has almost no resistance, so all the current will flow through that branch instead of flowing through the bulb.
<em>If</em> the lower switch were <u>opened</u>, THEN we would have a series circuit. Current would no longer have any other choice but to flow through the bulb, and the bulb would light.
Answer:
First of all the formula is F= uR,( force= static friction× reaction)
mass= 5+25=30
F= 50
R= mg(30×10)=300
u= ?
F=UR
u= F/R
u= 50/300=0.17N
Where r is the radius of balloon.
Here mass of woman = 68 kg
Mass of air displaced by a balloon with volume V = 1.29*V
Mass of helium inside balloon = 0.178*V
Total mass to be lifted by balloon = 68 +0.178*V
Buoyant force = 1.29V-0.178V=1.112V
So we have 1.112 V = 68+ 0.178*V
0.934 V = 68
V = 72.81 
\frac{4}{3} \pi r^{3}[/tex]= 72.81
r = 2.59 m
So radius of helium balloon = 2.59 m
