Answer:
2.73 km/s
Explanation:
The escape velocity of an object in the gravitational field of the moon is (on the surface of the planet)
where
is the gravitational constant
is the mass of the Moon
is the radius of the Moon
As we can see, the escape velocity does not depend on the mass of the lunar module.
Substituting the numbers into the formula, we find
Answer:
The percentage of its mechanical energy does the ball lose with each bounce is 23 %
Explanation:
Given data,
The tennis ball is released from the height, h = 4 m
After the third bounce it reaches height, h' = 183 cm
= 1.83 m
The total mechanical energy of the ball is equal to its maximum P.E
E = mgh
= 4 mg
At height h', the P.E becomes
E' = mgh'
= 1.83 mg
The percentage of change in energy the ball retains to its original energy,
ΔE % = 45 %
The ball retains only the 45% of its original energy after 3 bounces.
Therefore, the energy retains in each bounce is
∛ (0.45) = 0.77
The ball retains only the 77% of its original energy.
The energy lost to the floor is,
E = 100 - 77
= 23 %
Hence, the percentage of its mechanical energy does the ball lose with each bounce is 23 %
Answer:
By a factor 9
Explanation:
The intensity of a sound wave is proportional to the square of the amplitude of the wave:
where
I is the intensity
A is the amplitude of the wave
In this problem, the amplitude of the sound wave is increased by a factor 3:
A' = 3A
So the intensity would change by
So, the intensity would increase by a factor 9.