Answer:
The charge carried by the droplet is 
Explanation:
Given that,
Distance =8.4 cm
Time = 0.250 s
Suppose tiny droplets of oil acquire a small negative charge while dropping through a vacuum in an experiment. An electric field of magnitude
points straight down and if the mass of the droplet is 
We need to calculate the acceleration
Using equation of motion

Put the value into the formula



We need to calculate the charge carried by the droplet
Using formula of electric filed


Put the value into the formula


Hence, The charge carried by the droplet is 
Power is the work done per unit time. Therefore,

Therefore,
Answer:
A ball is thrown straight up with a speed of 30
m/s. What is the maximum height reached by
the ball?