Answer:
by making observation hope it's helpful
Answer:
Angular speed, 
Explanation:
It is given that,
The top of the leaning bell tower at Pisa, Italy, moved toward the south at an average rate of, v = 1.2 mm/yr

Velocity, 
Height of the tower, h = 55 m
The height of the tower is equivalent to the radius. Let
is the angular speed of the tower’s top about its base. The relation between the angular speed and the angular speed is given by :




So, the average angular speed of the tower’s top about its base is
. Hence, this is the required solution.
Answer:
the last one, the third one, and the first one.
Answer:
D. a person pulling a sled.
Explanation:
contact force only occurs when something directly comes in contact with another object.
a. is wrong because that is called magnetic force.
b. gravitational force
c. is an electrical force
Answer:
Minimum thickness will be 100 nm
Explanation:
We have given refractive index is n = 1.5
Wavelength of the light incidence
= 600 nm
We have to find the smallest thickness of the film so that there will be minimum light reflect
For minimum thickness of non reflecting film
, here t is thickness,
is wavelength and n is refractive index
Putting all values 
So minimum thickness will be 100 nm