Answer:
Work done to pull the piano upwards is 401250 J
Explanation:
Work is done against the gravity to pull the piano upwards
So here we can say that work done is

here we know that

also we know that
H = 75 m
now we have


Answer:
60,000m
Explanation:
Convert km/h to m/s by multiplying with 1000/3600.
Convert hours to seconds by multiplying with 3600.
Because displacement is a vector quantity and deals with the shortest distance between points, simply plug it into the equation s=vt.
The height at time t is given by
h(t) = -4.91t² + 34.3t + 1
When the ball reaches maximum height, its derivative, h'(t) = 0.
That is,
-2(4.91)t+34.3 = 0
-9.82t + 34.3 = 0
t = 3.4929 s
Note that h''(t) = -9.82 (negative) which confirms that h will be maximum.
The maximum height is
hmax = -4.91(3.4929)² + 34.3(3.4929) + 1
= 60.903 m
Answer:
The ball attains maximum height in 3.5 s (nearest tenth).
The ball attains a maximum height of 60.9 m (nearest tenth)
If you have a string that is fixed on both ends the amplitude of the oscillation must be zero at the beginning and the end of the string. Take a look at the pictures I have attached. It is clear that our fundamental harmonic will have the wavelength of:

All the higher harmonics are just multiples of the fundamental:

Three longest wavelengths are:
W = KE = 1/2m(v2f-v2i) also known as D just took the test