Answer:
yes friction is needed hope this helps might of been to long tho
Sound waves in air (and any fluid medium) are longitudinal waves because particles of the medium through which the sound is transported vibrate parallel to the direction that the sound wave moves.
Answer:(a)360N,(b)171N,(c)2.702m
Explanation:
(a)Maximum Friction Force =
=360 N
(b)Moment about Ground Point
(c)
Here maximum friction force can be 360 N
Therefore 
Where x is the maximum distance moved by man along the ladder
740x=2000
x=2.702m
Hyperbaric Oxygen Therapy (HBOT) is a medical treatment where the individual breathes in pure oxygen while in a pressurized room or through a tube. The HBOT treatment includes breathing 100% oxygen while under increased atmospheric pressure. It is used <span>for decompression sickness by scuba divers.</span>
Answer:
a) A = 3 cm, b) T = 0.4 s, f = 2.5 Hz,
2) A standing wave the displacement of the wave is canceled and only one oscillation remains
Explanation:
a) in an oscillatory movement the amplitude is the highest value of the signal in this case
A = 3 cm
b) the period of oscillation is the time it takes for the wave to repeat itself in this case
T = 0.4 s
the period is the inverse of the frequency
f = 1 /T
f = 1 /, 0.4
f = 2.5 Hz
2) a traveling wave is a wave for which as time increases the displacement increases, in the case of a transverse wave the oscillation is perpendicular to the displacement and in the case of a longitudinal wave the oscillation is in the same direction of the displacement.
A standing wave occurs when a traveling wave bounces off some object and there are two waves, one that travels in one direction and the other that travels in the opposite direction. In this case, the displacement of the wave is canceled and only one oscillation remains.
