Answer: Dependent Unit or System of Units
Explanation:
Density is calculated by dividing mass (Kg) by volume (L).
The unit of Density is Kg/L or one of their derivatives such as g/cm³.
When you punch holes in opposite corners of a milk carton filled with water which is hanging from a string, water will start to flow outside with a certain force. There will be a reaction equal and opposite to this force that will make the milk carton start to spin.
This is a typical example of water turbine that is used to demonstrate the third Newton's law.
1). The forces inside the atom are always, totally, completely, electrostatic forces. Those are so awesomely stronger than the gravitational forces that the gravitational ones are totally ignored, and it doesn't change a thing.
Parts 2 and 3 of this question are here to show us how the forces compare.
Part-2). The electrostatic force between a proton and an electron.
The constant in the formula is 9x10^9, and the elementary charge is 1.602 x 10^-19 Coulomb ... same charge on both particles, but opposite signs.
I worked through it 3 times and got 0.000105 N every time. So the best choice is 'C', even though we disagree by a factor of ten times. You'll see in part-3 that it really doesn't make any difference.
Part-3). Gravitational force between a proton and an electron.
The constant in Newton's gravity formula is 6.67x10^-11 . You'll have to look up the masses of the proton and the electron.
I got 2.163 x 10^-55 N ... exactly choice-C. yay !
Now, after we've slaved over a hot calculator all night, the thing that really amazes us is not only that the electrostatic force is stronger than the gravitational force, but HOW MUCH stronger ... 10^51 TIMES stronger. That's a thousand trillion trillion trillion trillion times stronger !
That's why it has no effect on the measurements if we just forget all about the gravitational forces inside the atom.
Answer:
The coefficient of static friction between the coin and the turntable is 0.51
Explanation:
at the time of the slip:
centripetal force = frictional force
mv^2/r = x*m*980
v^2/r = 980x
x = v^2/980r
= [(120)^2]/[980*29]
= 0.51
Therefore, The coefficient of static friction between the coin and the turntable is 0.51
Angles will probably be 96° 35° and 49°
I tried to explain it with the working out, just re arrange the cosine rule for angles instead of side lengths.
if you need it explaining at all just message me :)
hoped it helped
