To develop this problem we will apply the considerations made through the concept of Doppler effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. At first the source is moving towards the observer. Than the perceived frequency at first
Where F is the actual frequency and v is the velocity of the ambulance
Now the source is moving away from the observer.
We are also so told the perceived frequency decreases by 11.9%
Equating,
Solving for V,
Answer:
they are used in periscopes,for signalling,in kaleidoscopes,to see round dangerous bends
Explanation:
To find the number of neutrons in an isotope, subtract the number of protons from the atomic mass of the isotope. The atomic number of the element equals the number of protons.
Answer:
Explanation:
Given that,
A lady falling has a final velocity of 4m/s
v = 4m/s
Mass of the lady is 60kg.
m = 60kg
Using conservation of energy, the potential energy of the body from the point where the lady is dropping is converted to the final kinetic energy of the lady.
Therefore,
P.E = K.E(final) = ½mv²
P.E = ½ × 60 × 4²
P.E = 480 J.