Answer:
The focal length of the appropriate corrective lens is 35.71 cm.
The power of the appropriate corrective lens is 0.028 D.
Explanation:
The expression for the lens formula is as follows;

Here, f is the focal length, u is the object distance and v is the image distance.
It is given in the problem that the given lens is corrective lens. Then, it will form an upright and virtual image at the near point of person's eye. The near point of a person's eye is 71.4 cm. To see objects clearly at a distance of 24.0 cm, the corrective lens is used.
Put v= -71.4 cm and u= 24.0 cm in the above expression.


f= 35.71 cm
Therefore, the focal length of the corrective lens is 35.71 cm.
The expression for the power of the lens is as follows;

Here, p is the power of the lens.
Put f= 35.71 cm.

p=0.028 D
Therefore, the power of the corrective lens is 0.028 D.
D = distance between th two trains at the start of the motion = 100 miles
V = speed of the faster train towards slower train = 60 mph
v = speed of the slower train towards faster train = 40 mph
t = time taken by the two trains to collide = ?
time taken by the two trains to collide is given as
t = D/(V + v)
t = 100/(60 + 40) = 1 h
v' = speed of the bird = 90 mph
d = distance traveled by the bird
distance traveled by the bird is given as
d = v' t
d = 90 x 1
d = 90 miles
Answer:
Explanation:
Given
Weight of person
At highest point Magnitude of the normal force
net force at highest point
where
centripetal force
Normal Force
Negative sign shows force is in upward direction
At bottom point centripetal force is towards the bottom
Answer:
I = M R^2 is the moment of inertia about a point that is a distance R from the center of mass (uniform distributed mass).
The moment of inertia about the center of a sphere is 2 / 5 M R^2.
By the parallel axis theorem the moment of inertia about a point on the rim of the sphere is I = 2/5 M R^2 + M R^2 = 7/5 M R^2
I = 7/5 * 20 kg * .2^2 m = 1.12 kg m^2