Answer:
The net force on the box is 2 N to the left.
The box will move to the left.
The acceleration on the box is 0.5 m/s^2 to the left.
Explanation:
Let's say movement to the right is positive and left is negative.
Bob: +10 N
John: -12 N
Add those together and you get a net force of -2 N, and the negative sign means that the box is moving to the left.
For the acceleration:
Fnet = ma
-2 = (4 kg)a
a = -0.5 m/s^2
Again, the negative sign in this answer means the box is being accelerated to the left.
Since,
Speed = Frequency * WaveLength
=> WaveLength = Speed / Frequency --- (A)
Frequency = 13.0 kHz.
As the radio waves are electromagnetic waves, their speed is equals to the speed of light. Therefore,
Speed = C =

Plug in the values in equation(A):
A => WaveLength =
Ans: Wavelength = 23.077 kilometers.-i
Answer:
They are both correct.
Explanation:
The density of an object is defined as the ratio of its mass to its volume. This implies that the density of the object is both proportional to the mass and also to the volume of the object. John only mentioned mass which is correct. Linda mentioned the second variable on which density depends which is the volume of the object.
Hence considering the both statements objectively, one can say that they are both correct.
Answer:
Therefore the correct statement is B.
Explanation:
In the interference and diffraction phenomena, the natural wave of electromagnetic radiation must be taken into account, the wave front that advances towards the slit can be considered as when it reaches it behaves like a series of wave emitters, each slightly out of phase from the previous one, following the Huygens principle that states that each point is compiled as a source of secondary waves.
The sum of all these waves results in the diffraction curve of the slit that has the shape
I = Io sin² θ /θ²
Where the angle is a function of the wavelength and the width of the slit.
From the above, the interference phenomenon can be treated as the sum of two diffraction phenomena displaced a distance equal to the separation of the slits (d)
Therefore the correct statement is B