<span>So we want to know which statement is true for the body of mass m=2000kg that is lifted to a height of h=15m in t=15 s. Lets calculate each of the following: Gravity force on the body is F=m*g=2000*9.81=19620 N so a is FALSE. Potential energy of the body when it is lifted to the height of 15 m is Ep=m*g*h=2000*9.81*15=294300 J so b is FALSE. Work to lift the body is: W=Fg*h=2000*9.81*15= Ep=294300 J so c is FALSE. Power P=W/t=294300/15=19620 W So d is TRUE. </span>
Explanation:
The critical velocity is that velocity of liquid flow, up to which its flow is streamlined (laminar)& above which its flow becomes turbulent. It's denoted by Vc & it depends upon: Coefficient of viscosity of liquid (η) Density of liquid. Radius of the tube.
Four of them pass a point every second.
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!
