<u>Answer:</u> Below 12m of depth, the submarine has to submerge so that it would not be swayed by surface waves
<u>Explanation:</u>
To avoid the surface waves, a submarine has to submerge below the wave base. It is the position below which the motion of the waves is negligible.
This wave base is equal to half of the wavelength. The equation becomes:
Wave base =
We are given:
Wavelength = 24 m
Putting values in above equation, we get:
Wave base =
Hence, below 12m of depth, the submarine has to submerge so that it would not be swayed by surface waves
Answer:
The value is
Explanation:
From the question we are told that
The speed is
The radius of the earth is
Generally the circumfernce of the earth is mathematically evaluated as
=>
=>
Generally the time taken is mathematically represented as
Converting to days
=>
Answer:
The moment is -78.4 N-m (clockwise).
Explanation:
Given:
Mass of the object (m) = 20 kg
Distance of the object from the knee joint (d) = 0.4 m
Weight of leg is not considered.
Acceleration due to gravity (g) = 9.8 m/s²
Now, weight of the object is equal to the product of its mass and acceleration due to gravity. So,
Weight = Mass × Acceleration due to gravity
=
We know that, moment of a force about a point is defined as the product of force applied and the perpendicular distance between the point and the line of application of force.
Moment of the given weight about the knee joint is given as:
Moment about knee joint = Weight × Distance from knee joint to weight
Moment about knee joint = 196 × 0.4 = 78.4 Nm
Now, from the diagram below, we can observe that, the weight acts vertically down and thus the sense of rotation about the knee joint at point O is clockwise. So, moment is negative.
Therefore, the moment is -78.4 N-m (clockwise).
