Answer:
λ = hv
If frequency is doubled :
λ = h × 2v
λ = 2hv
Thus wavelength is doubled
The sun <u><em>appears</em></u> brighter than any other star.
(It isn't really, but it looks that way because it's much much much much much much closer to us than any other star.)
Answer:
A) 
B) 
Explanation:
Given:
mass of car, 
A)
frequency of spring oscillation, 
We knkow the formula for spring oscillation frequency:




Now as we know that the springs are in parallel and their stiffness constant gets added up in parallel.
<u>So, the stiffness of each spring is (as they are identical):</u>



B)
given that 4 passengers of mass 70 kg each are in the car, then the oscillation frequency:



Answer:
Acceleration = Change in Velocity/Time
Change in Velocity = 36-18 = 18 km/h=5 m/s
Time= 5 Seconds
Acceleration = 5/5= 1 m/s2
Equation of motion,s=ut+(1/2)at2
u=18 km/h=5 m/s
t=5 s
a=1 m/s2
s= (5*5)+(1/2*1*5*5)
s=25+12.5 i.e., s=37.5 m
Hope you are clear with my explanations
The answer to your question is "A. a lower frequency of the siren.
Because the person in back of the ambulance will hear a lower frequency of the siren. This is because the waves are stretched out. A longer wavelength results in a lower frequency.