Answer:
3 s.
Explanation:
Echo is defined as the repetition of a sound produced by the reflection of sound waves from an obstructing surface like a wall, mountain etc.
v = f*lambda
Where,
Lambda = wavelength of the wave
f = frequency of the wave = 1/t
v = velocity of the wave.
Distance there and back = initial ditance * 2
= 525 x 2
= 1050.
Time taken, t = lamda/velocity
= 1050 / 350
= 3 s.
So the delay is 3 seconds.
Answer:
ΔF=125.22 %
Explanation:
We know that drag force on the car given as

=Drag coefficient
A=Projected area
v=Velocity
ρ=Density
All other quantity are constant so we can say that drag force and velocity can be given as

Now by putting the values



Percentage Change in the drag force



ΔF=125.22 %
Therefore force will increase by 125.22 %.
Answer:
t = S / V where S is distance sound travels and V the speed of sound
S = 20 + 20 - v t where v is speed of bat and t time to hear echo
S = 40 - v t
t = (40 - S) / v = (40 - V t) / v substituting S from 1st equation
v t + V t = 40
t = 40 / (v + V) = 40 / (340 + 2) = .117 sec = 117 ms
Weight of a person on the earth is given by,
W= mg,
Where, g is the gravitational acceleration of the earth and m is the mass of the person.
Gravitational acceleration of the moon is one-sixth of the earth.
Therefore, the weight of a astronaut who goes to the moon will be one sixth of that on earth. Hence, the astronaut will weight less.
In order to change the colour of the light, you would need to change both the wavelength and frequency of light, as light in the visible spectrum, have their own unique wavelengths that they occur in along with the measure of frequency, which measures the number of cycles or turns a wave can occur from trough to trough or crest to crest within a given period of time.