Answer:
nail will stop after traveling 1000 m
Explanation:
We have given mass m = 50 gram = 0.05 kg
Frictional force which is used to stop the mass F = 62.5 kN
Initial velocity is given u = 50 m/sec
From newton's law force is equal to F = ma, here m is mass and a is acceleration
So 
As finally nail stops so final velocity v = 0 m/sec
From third equation of motion 
So 
s = 1000 m
So nail will stop after traveling 1000 m
The force that causes you to fall forward is Inertia.
<span>Displacement is the difference between the initial position and the FINAL position of an object.
Hope this helps!</span>
The frequency of the human ear canal is 2.92 kHz.
Explanation:
As the ear canal is like a tube with open at one end, the wavelength of sound passing through this tube will propagate 4 times its length of the tube. So wavelength of the sound wave will be equal to four times the length of the tube. Then the frequency can be easily determined by finding the ratio of velocity of sound to wavelength. As the velocity of sound is given as 339 m/s, then the wavelength of the sound wave propagating through the ear canal is
Wavelength=4*Length of the ear canal
As length of the ear canal is given as 2.9 cm, it should be converted into meter as follows:

Then the frequency is determined as
f=c/λ=339/0.116=2922 Hz=2.92 kHz.
So, the frequency of the human ear canal is 2.92 kHz.
Answer:
The answer is C)The force of gravity from Earth acting on the spacecraft decreased because the distance from Earth increased.
Explanation:
Gravity, a force, is dependent on the mass of the object exerting the gravity and the distance of an outside object from that object. The larger the object, the more gravity it will exert on an outside object. This force decreases as you move away from the object, but it will always still exist and never be equal to 0.