Answer:
100 Ω
Explanation:
Given that
Open circuit voltage, V = 1 V
Short circuit current, I = 10 mA
Source resistance R, = ?
This is rather a straight forward question. Remember Ohms Law? Current being directly proportional to the voltage and inversely proportional to the resistance?
Yeah, that's the formula we'd be using.
Ohms Law states that V = IR, and thus, if we make R subject of the formula, we have
R = V / I, on substituting the values, we have
R = 1 / 10*10^-3
R = 1 / 0.01
R = 100 Ω
When an object is above the Earth's surface it has gravitational potential energy (GPE). The amount of GPE an object has depends on its mass and its height above the Earth's surface.
The weight of an object is the size of the force of gravity pulling the object down. When an object falls it transfers GPE to KE (kinetic energy).
a. 7.0 m/s
First of all, we need to convert the angular speed (1200 rpm) from rpm to rad/s:

Now we know that the row is located 5.6 cm from the centre of the disc:
r = 5.6 cm = 0.056 m
So we can find the tangential speed of the row as the product between the angular speed and the distance of the row from the centre of the circle:

b. 
The acceleration of the row of data (centripetal acceleration) is given by

where we have
v = 7.0 m/s is the tangential speed
r = 0.056 m is the distance of the row from the centre of the trajectory
Substituting numbers into the formula, we find

Work = (500N)(15m)=7500J Power= (7500J)/(20s) =375 W
Hopefully this helps
Cations are positively charged ions. And for positive charged ions, it means the positive charges, protons, are more than the negative charges, the electrons.
Therefore Cations have fewer electrons than protons.
So the answer is: c. electrons; protons.