Answer:
f=force m=mass and a=acceleration
In a series circuit, a common current flows through all the components of the circuit. While in a parallel circuit, a different amount of current flows through each parallel branch of the circuit. Whereas in the parallel circuit, the same voltage exists across the multiple components in the circuit.
Hope It Helps!
Distance = speed X time
In this example, the speed of the airplane = 840km. The time (that the question is asking)is how far can it travel in 1 hour.
So just plug in your numbers.
Distance = 840km X 1 hour = 840km/hour or 840km for short.
Answer:

Explanation:
The water droplet is initially neutral, it will obtain a 40 nC of charge when a charge of -40 nC is removed from the water droplet.
The charge on one electron, 
Let the N number of electrons have charge -40 nC, such that,
Now, mass of one electron = 
Therefore, mass of N electrons = 
It is the mass of the of the water droplet that must be removed in order to obtain a charge of 40 nC.
Let it is m times the total mass of the droplet which is 
Then,

It is the required fraction of mass of the droplet.
The picture shows an example of velocity