Answer:
Ep = 3924 [J]
Explanation:
To calculate this value we must use the definition of potential energy which tells us that it is the product of mass by the acceleration of gravity by height.

where:
Ep = potential energy [J] (units of Joules)
m = mass = 40 [kg]
g = gravity acceleration = 9.81 [m/s²]
h = elevation = 10 [m]
![E_{p} =40*9.81*10\\E_{p} = 3924 [J]](https://tex.z-dn.net/?f=E_%7Bp%7D%20%3D40%2A9.81%2A10%5C%5CE_%7Bp%7D%20%3D%203924%20%5BJ%5D)
 
        
             
        
        
        
The answer for this question is A
        
             
        
        
        
Answer:

Explanation:
We are given that a parallel- plate capacitor is charged to a potential difference V and then disconnected from the voltage source.
1 m =100 cm 
Surface area =S=


We have to find the charge Q on the positive plates of the capacitor.
V=Initial voltage between plates
d=Initial distance between plates 
Initial Capacitance of capacitor 

Capacitance of capacitor after moving plates


Potential difference between plates after moving








Hence, the charge on positive plate of capacitor=
 
        
             
        
        
        
Answer:
Acceleration = 9 × 10^5 m/s^2 ( deceleration )
Explanation:
From the first equation of motion:
V = u + at
15000 = 30000 + 60a
a = ( 15000-30000)/60
a = 9 × 10^5 m/s^2