Answer:
The observer detects light of wavelength is 115 nm.
(b) is correct option
Explanation:
Given that,
Wavelength of source = 500 nm
Velocity = 0.90 c
We need to calculate the wavelength of observer
Using Doppler effect
Where,
Hence, The observer detects light of wavelength is 115 nm.
Answer:
u= 29.43 m/s
h=44.14 m
Explanation:
Given that
t= 3 s
We know that acceleration due to gravity ,g = 9.81 m/s² (Downward)
Initial velocity = u
Final velocity ,v= 0 (At maximum height)
We know v = u +a t
v=final velocity
u=initial velocity
a=Acceleration
Now by putting the values in the above equation
0 = u - 9.81 x 3
u= 29.43 m/s
The maximum height h is given as
v² = u ² - 2 g h
0² = 29.43 ² - 2 x 9.81 x h
h=44.14 m