<span>At first when the car is at the datum
point where is no elevation, the kinetic energy increases while the potential
energy is zero. As it travel the path and goes upward the kinetic enrgy
decreases while the potential energy increases. When it goes down again the
kinetic enrgy increases again while the potential energy decreases </span>
Answer:

Explanation:
= Permittivity of free space = 
= Surface charge density = 
= 0.57-0.26
q = Charge = 
m = Mass of object = 
Electric field due to a sheet is given by

Electric field is given by

Voltage is given by

Kinetic energy is given by


The initial speed of the object is 
I believe it is water that is the medium for beach erosion
Answer:
15 cm
Explanation:
= Diameter of the coin = 15 mm
= Diameter of the image of coin = 5 mm
= distance of the coin from mirror = 15 cm
= distance of the image of coin from mirror = ?
Using the equation


= - 5 cm
= radius of curvature
Using the mirror equation


= - 15 cm