Answer:
phase difference 
Explanation:
Phase difference is expressed as 

Where,
= phase difference
wavelength = 460nm
path difference = 920 nm

therefore
phase difference 
Answer:
789.8 W
Explanation:
mass of the cab = 1400 kg, the counter weight of the elevator = 930 kg
weight of the cab = 1400 × 9.81 where weight = mg and m is mass and g is acceleration due to gravity.
weight of the cab = 13734 N
counter weight of the elevator = 930 × 9.81 = 9123.3 N
the exerted force of the elevator = weight of the cab - counter weight of the elevator = 13734 - 9123.3 = 4610.7 N
Average power by the motor P = F × v = F × distance / time
where v is speed in m/s, and time is in seconds
P = 4610.7 × 37 / ( 3.6 × 60) = 789.80 W
where (3.6 × 60 ) is the time in seconds
The electric field intensity generated by a single point charge is given by

where
k is the Coulomb's constant
q is the charge
r is the distance from the charge
In this problem, the charge is
and we are asked to calculate the field at distance
, so the electric field is

Answer:
C.
Explanation:
The definition of a fossil is the preserved remains of a prehistoric organism or is slang for someone or something that is outdated. An example of a fossil is the preserved remains from a prehistoric organism that have been preserved inside rock.