Answer:
A force of 20N acts on each cm^2 of area
Answer:
option (d)
Explanation:
A concave mirror always forms a real and inverted image of an object except when the object placed between pole and focus of the mirror.
When the object is placed beyond the centre of curvature, it forms a image which is smaller than the object but it is real and inverted in nature.
Air resistance opposes the motion of falling objects. Dense air prefers to stay at low heights. More dense the air is, more air resistance it produces. Hence acceleration of falling objects decreases. Hope this helps!
I don't know your statement, but one explanation for this is that Russia is mostly located on land, away from water and Florida is surrounded by water.
Water takes up the heat from the environment, so it has the effect of making the temperatures of objects around it milder: cooling down when hot, warming up when too cold.
Answer:
Explanation:
a ) F = (-kx + kx³/a²)
intensity of field
I = F / m
= (-kx + kx³/a²) / m
If U be potential function
- dU / dx = (-kx + kx³/a²) / m
U(x) = ∫ (kx - kx³/a²) / m dx
= k/m ( x²/2 - x⁴/4a²)
b )
For equilibrium points , U is either maximum or minimum .
dU / dx = x - 4x³/4a² = 0
x = ± a.
dU / dx = x - x³/a²
Again differentiating
d²U / dx² = 1 - 3x² / a²
Put the value of x = ± a.
we get
d²U / dx² = -2 ( negative )
So at x = ± a , potential energy U is maximum.
c )
U = k/m ( x²/2 - x⁴/4a²)
When x =0 , U = 0
When x= ± a.
U is maximum
So the shape of the U-x curve is like a bowl centered at x = 0
d ) Maximum potential energy
put x = a or -a in
U(max) = k/m ( x²/2 - x⁴/4a²)
= k/m ( a² / 2 - a⁴/4a²)
= k/m ( a² / 2 - a²/4)
a²k / 4m
This is the maximum total energy where kinetic energy is zero.