Answer:
B
Explanation:
Is the equilibrium stable or unstable for the third charge
The Tools Used to Measure Density
Scale. Mass is one of the most easily obtained measurements. ...
Graduated Cylinder. The most accurate way to determine an object's volume, especially in the case of an irregularly shaped object, is to immerse it in water and measure the amount of water it displaces. ...
Calculating Density. ...
Hydrometer. ...
The Value of Density.
Answer:
Explanation:
Given
Train travels towards south with a velocity if 
Rain makes an angle of
with vertical
If an observer sees the drop fall perfectly vertical i.e. horizontal component of rain velocity is equal to train velocity
suppose
is the velocity of rain with respect to ground then



Therefore velocity of rain drops is 27.36 m/s
Well, the surface of still water has surface tension. If there isn't enough mass or weight to break the surface tension, the object will float.