Answer:
Mediums in which the speed of sound is different generally have differing acoustic impedances, so that, when a sound wave strikes an interface between
Explanation:The propagation of a wave through a medium will depend on the properties of the medium. For example, waves of different frequencies may travel
Answer:
The free end of the blade has a tangential velocity of about 88.19 m/s
Explanation:
The angular velocity of the blades is 
since the blades are 80 m long, then the tangential velocity of the free end of the blade is:

Answer:
It represents the change in charge Q from time t = a to t = b
Explanation:
As given in the question the current is defined as the derivative of charge.
I(t) = dQ(t)/dt ..... (i)
But if we take the inegral of the equation (i) for the time interval from t=a to
t =b we get
Q =∫_a^b▒〖I(t) 〗 dt
which shows the change in charge Q from time t = a to t = b. Form here we can say that, change in charge is defiend as the integral of current for specific interval of time.
Answer:
18750 kg-m/s
Explanation:
Momentum = mass x velocity
Answer:
Explanation:
a ) starting from rest , so u = o and initial kinetic energy = 0 .
Let mass of the skier = m
Kinetic energy gained = potential energy lost
= mgh = mg l sinθ
= m x 9.8 x 70 x sin 30
= 343 m
Total kinetic energy at the base = 343 m + 0 = 343 m .
b )
In this case initial kinetic energy = 1/2 m v²
= .5 x m x 2.5²
= 3.125 m
Total kinetic energy at the base
= 3.125 m + 343 m
= 346.125 m
c ) It is not surprising as energy gained due to gravitational force by the earth is enormous . So component of energy gained due to gravitational force far exceeds the initial kinetic energy . Still in a competitive event , the fractional initial kinetic energy may be the deciding factor .