Answer:

Explanation:
The roller coaster begins with maximum kinetic energy and no gravitational potential energy. The gravitational potential energy reaches its maximum when roller coaster is upside down at the top of the circle. The physical model for the roller coaster is constructed by means of the Principle of Energy Conservation:

The minimum velocity is:

Let assume that radio of curvature is measured in meters. Hence:


Answer:
The electric field at origin is 3600 N/C
Solution:
As per the question:
Charge density of rod 1, 
Charge density of rod 2, 
Now,
To calculate the electric field at origin:
We know that the electric field due to a long rod is given by:

Also,
(1)
where
K = electrostatic constant = 
R = Distance
= linear charge density
Now,
In case, the charge is positive, the electric field is away from the rod and towards it if the charge is negative.
At x = - 1 cm = - 0.01 m:
Using eqn (1):

(towards)
Now, at x = 1 cm = 0.01 m :
Using eqn (1):

(towards)
Now, the total field at the origin is the sum of both the fields:

Answer:
#_electrons = 2 10¹⁰ electrons
Explanation:
For this exercise we can use a direct rule of three proportions rule. If an electron has a charge of 1.6 10⁻¹⁹ C how many electrons have a charge of 3.2 10⁻⁹ C
#_electrons = 3.2 10⁻⁹ (
)
#_electrons = 2 10¹⁰ electrons
Answer:
The diameter of the camera aperture must be greater than or equal to 1.49m
Explanation:
Let the distance separating two objects, x = 6.0 cm = 0.06 m
The distance between the observer and the two objects, d = 160 km = 160000 m
Let ∅ = minimum angular separation between the two objects that the satellite can resolve
tan( ∅) = x/d
Since there is minimum angular separation, tan( ∅) ≈∅
∅ = x/d
∅ = 0.06/160000
∅ = 3.75 * 10⁻⁷rad
For the satellite to be able to resolve the objects,
D ≥ 1.22λ/∅
λ = 560 nm = 560 * 10⁻⁹
D ≥ 1.22 * (560 * 10⁻⁹)/(3.75 * 10⁻⁷)
D ≥ 149.33 * 10⁻² m
D ≥ 1.49 m
Explanation:
Image distance, v = -17 cm (-ve for virtual image)
Radius of curvature of concave mirror, R = 39 cm
Focal length, f = -19.5 cm (-ve for a concave mirror)
(a) Using mirror's formula as :


u = 132.6 cm
So, the object is placed 132.6 cm in front of the mirror.
(b) Magnification of the mirror, 

m = -0.128
Hence, this is the required solution.