The shaft is 78m approximately deep. The correct option is D which is 78 meters
<h3>
What are Sound Waves ?</h3>
Sound waves are longitudinal. That is, the direction of the waves is parallel to the direction of its propagation of particles.
Given that a boy finds an abandoned mine shaft in the woods, and wants to know how deep the hole is. He drops in a stone, and counts 4 seconds before he hears the "plunk" of the stone hitting the bottom of the shaft.
- The speed of the sound V = 330m/s
- The time it takes the sound to reach the top = t
Speed V = distance / time
330 = h/t
Make t the subject of formula
t = h/330
As the stone is dropped, initial velocity = 0, Using the formula
h = 1/2gT²
But T = 4 - t
T = 4 approximately
Substitute all the parameters
h = 1/2 × 9.8 × (4)²
h = 4.9 × (16)
h = 78.4m
Therefore, the shaft is 78m approximately deep. The correct option is D which is 78 meters
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When analyzing inelastic collisions, we need to consider the law of conservation of momentum, which states that the total momentum, p, of the closed system is a constant. In the case of inelastic collisions, the momentum of the combined mass after the collision is equal to the sum of the momentum of each of the initial masses.
p1+p2+...=pf
In our case we only have two masses, which makes our problem fairly simple. Lets plug in the formula for momentum; p=mv.
m1v1+m2v2=(m1+m2)vf
To find the velocity of the combined mass we simply rearrange the terms.
vf=m1v1+m2v2m1+m2
Plug in the values given in the problem.
vf=(3.0kg)(1.4m/s)+(2.0kg)(0m/s)03.0kg+2.0kg
vf=.84m/s
P=mv
2087.4 kg meter/second
C. The potential energy would double.
Explanation:
The potential energy of an object is the energy at rest. it is the product of its mass, gravity and height.
Potential energy = mgh
where m is the mass
g is the acceleration due to gravity
h is the height
From the above, potential energy is proportional to the height. If any change in any of the parameters will directly affect the potential energy. This implies that if height is double, the potential energy is doubled.
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Potential energy brainly.com/question/10770261
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Answer:
The length is 
and the angle is 
Explanation:
The period 
of the pendulum is related to its length 
by
where 
is the acceleration due to gravity.
Solving for we get
putting in 
and we get:
There are two forces acting on the pendulum: The gravitational force 
and the 
student's force. Therefore, the angular displacement 
that these forces give is
putting in 
, 
, and we get
