Answer:
Newton's F=ma, which means the force (F) acting on an object is equal to the mass (m) of an object times its acceleration (a)
The wavelength of the third resonance of the closed organ pipe is equal to the ratio between the speed of sound and the frequency of the 3rd harmonic:

The relationship between length of a closed pipe and wavelength of the standing waves inside is:

where n is the number of the harmonic. In this case, n=3, so the length of the pipe is

The force that acts on all objects, all the time on Earth is gravitational force.
The force that surface exert on an object perpendicularly is normal reaction.
<h3>What force acts on all objects, all the time on Earth?</h3>
- Force due to gravity is gravitational pull on objects due to its position on earth's surface.
The force due to gravity on object's is calculated by applying Newton's second law of motion as follows;
F = mg
where;
- m is the mass of the object
- g is acceleration due to gravity
The force that surface exert on an object perpendicularly is normal reaction.
Thus, the force that acts on all objects, all the time on Earth is gravitational force.
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Answer:
24 N
Explanation:
= mass of the cube = 
Consider the three cubes together as one.
= mass of the three cubes together = 
= acceleration of the combination = 2 ms⁻²
= Force applied on the combination
Using Newton's second law

= Force by the left cube on the middle cube
Consider the forces acting on left cube, from the force diagram, we have

For a curved mirror, all points have the same normal and the angle of incidence is also equal to the angle of reflection.
According to the laws of reflection, the incident ray, reflected ray and normal all lie on the same plane. For a curved mirror, the normal remains the same at all points along the curved mirror.
Again, the angle made between the incident ray and the normal is the same as the angle made between the reflected ray and the normal. Therefore, the angle of reflection is equal to the angle of incidence.
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