Answer:
a) 6.95 m/s
b) 1.42 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²

a) The vertical speed when it leaves the ground. is 6.95 m/s

Time taken to reach the maximum height is 0.71 seconds

Time taken to reach the ground from the maximum height is 0.71 seconds
b) Time it stayed in the air is 0.71+0.71 = 1.42 seconds
5.4*10^-19 C
Explanation:
For the purposes of this question, charges essentially come in packages that are the size of an electron (or proton since they have the same magnitude of charge). The charge on an electron is -1.6*10^-19
Therefore, any object should have a charge that is a multiple of the charge of an electron - It would not make sense to have a charge equivalent to 1.5 electrons since you can't exactly split the electron in half. So the charge of any integer number of electrons can be transferred to another object.
Charge = q(electron)*n(#electrons)
Since 5.4/1.6 = 3.375, we know that it can not be the right answer because the answer is not an integer.
If you divide every other option listed by the charge of an electron, you will get an integer number.
(16*10^-19 C)/(1.6*10^-19C) = 10
(-6.4*10^-19 C)/(1.6*10^-19C) = -4
(4.8*10^-19 C)/(1.6*10^-19C) = 3
(5.4*10^-19 C)/(1.6*10^-19C) = 3.375
(3.2*10^-19C)/(1.6*10^-19C) = 2
etc.
I hope this helps!
ANSWER:
The easiest way to get a fairly accurate measure of your water flow rate is to time yourself filling up a bucket. So for example if you fill up a 10 litre bucket in 1.5 minutes, then your flow rate will be: 10/1.5 = 6.66 Litres per minute.