Answer:

Explanation:
Here we know that the EMF induced in this Field is given as

here B = perpendicular component of magnetic field
v = speed of the bird
L = length of the wings
now we have



now we have


First of all Longitudinal waves is a matter in the medium that moves parallel to the direction of the wave travels.
1st example: sound travels parallel.
2nd example: when you talk you will here your voice again. because all the frequency bounce back to you.
In the other hand Transverse wave matter in the medium moves perpendicular to direction the wave travels.
For example: light is a good example of transverse wave.
Answer: 3 square feet
Explanation: I took the test
Answer:
Explanation:
(ΔK + ΔUg + ΔUs + ΔEch + ΔEth = W)
ΔK is increase in kinetic energy . As the athelete is lifting the barbell at constant speed change in kinetic energy is zero .
ΔK = 0
ΔUg is change in potential energy . It will be positive as weight is being lifted so its potential energy is increasing .
ΔUg = positive
ΔUs is change in the potential energy of sportsperson . It is zero since there is no change in the height of athlete .
ΔUs = 0
ΔEth is change in the energy of earth . Here earth is doing negative work . It is so because it is exerting force downwards and displacement is upwards . Hence it is doing negative work . Hence
ΔEth = negative .
b )
work done by athlete
= 400 x 2 = 800 J
energy output = 800 J
c )
It is 25% of metabolic energy output of his body
so metalic energy output of body
= 4x 800 J .
3200 J
power = energy output / time
= 3200 / 1.6
= 2000 W .
d )
1 ) Since he is doing same amount of work , his metabolic energy output is same as that in earlier case .
2 ) Since he is doing the same exercise in less time so his power is increased . Hence in the second day his power is more .