Answer:
The frequency of the sound wave is 800Hz
The speed of sound in a is about 340m/s.
Velocity = frequency x wavelength
making wavelength the subject formula
wavelength = Velocity/frequency.
wavelength = 340/800
wavelength = 0.425m.
B . it should be convert energy.
Answer
4.8 N
If the box is moving with a constant velocity, then we can say that the system is in equilibrium. This is because if the external force (F->) was greater than other forces the box would be accelerating. This tells us that this force (F->) is just enough to overcome friction and so it must be equal to 4.8 N.
The normal force has no effect to the horizontal velocities or forces. It is equal to -Weight. That is -74 N. The negative sign shows that the force is in opposite direction.
<span>I believe it's insulation.</span>