It is given that by using track and cart we can record the time and the distance travelled and also the speed of the cart can be recorded. With all this data we can solve questions on the laws of motion.
Like using the first law of motion we can determine the force of gravity acting on the cart that has moved a certain distance and the velocity or the speed of card has already been registered and since time is known putting the values in formula would help us calculate the gravitational pull acting on cart.
Answer:

Explanation:
We are given that
Surface area of membrane=
Thickness of membrane=
Assume that membrane behave like a parallel plate capacitor.
Dielectric constant=5.9
Potential difference between surfaces=85.9 mV
We have to find the charge resides on the outer surface of membrane.
Capacitance between parallel plate capacitor is given by

Substitute the values then we get
Capacitance between parallel plate capacitor=

V=


Hence, the charge resides on the outer surface=
Answer:
I don't really know
Explanation:
I really wanted to help you, but then I realized i didnt know how to
Answer:
Hello your question is incomplete attached below is the complete question
Answer : x ( acceleration of mass 4m ) = 
The top pulley rotates because it has to keep the center of mass of the system at equilibrium
Explanation:
Given data:
mass suspended = 4 meters
mass suspended at other end = 3 meters
first we have to express the kinetic and potential energy equations
The general kinetic energy of the system can be written as
T = 
T =
also the general potential energy can be expressed as
U = 
The Lagrangian of the problem can now be setup as

next we will take the Euler-Lagrange equation for the generalized equations :
Euler-Lagrange equation = 
solving the equations simultaneously
x ( acceleration of mass 4m ) = 
The top pulley rotates because it has to keep the center of mass of the system at equilibrium