Answer:
Charge Z can be placed at <em>x</em> = -2.7 m or at <em>x</em> = 0.27 m.
Explanation:
The Coulomb force between two charges,
and
, separated by a distance,
, is given

<em>k</em> is a constant.
For the charge Z to be at equilibrium, the force exerted on it by charge X must be equal and opposite to the force exerted on it by charge Y.
It is to be placed along the <em>x</em>-axis. Hence, it is on the same line as charges X and Y.
Let the charge on Z be <em>Q</em>. It is positive.
Let the distance from charge X be <em>x m.</em> Then the distance from charge Y will be (0.60 - <em>x</em>) m.
Force due to charge X

Force due to charge Y

Since both forces are equal and opposite,







Applying the quadratic formula,

or 
Charge Z can be placed at <em>x</em> = -2.7 m or at <em>x</em> = 0.27 m
Answer: 52%
Explanation:
1W = 1 J/s
motor input is 10000 J/s
Potential energy change
PE = 955(9.81)(25.0) = 234,213.75
power needed to change the PE in that time
P = 234,213.75/ 45 = 5,204.75 Watts
motor is 5204.75 / 10000 = 0.520475 or 52% efficient
Mass is <span>is a dimensionless quantity representing the amount of matter in a particle or object. The more mass something has, the more energy is used to lift it.</span>