Answer:
λ = 437 m.
Explanation:
Answer:
Explanation:
b ) The problem is based on Doppler's effect of sound
f = f₀ x (V - v₀) /( )
f is apparent frequency ,f₀ is real frequency , V is velocity of sound , v₀ is velocity of observer going away , is velocity of source going away
778 = 840 x (340 - 14)/ (340 + )
340 + = 341.18
= 1.18 m /s
it will go away from the observer or the cyclist.
speed of train = 1.18 m /s
a )
For a stationary observer v₀ = 0
f = f₀ x V /( )
= 840 x 340 / (340 + 1.180)
= 837 Hz
Answer:
The person with locked legs will experience greater impact force.
Explanation:
Let the two persons be of nearly equal mass (say m)
The final velocity of an object (person) dropped from a height H (here 2 meters) is given by,
( = acceleration due to gravity)
which can be derived from Newton's equation of motion,
Now, the time taken (say ) for the momentum (
) to change to zero will be more in the case of the person who bends his legs on impact than who keeps his legs locked.
We know that,
Naturally, the person who bends his legs will experience lesser force since is larger.