I think It would be C. Checking a prediction. Sorry if I’m wrong
Answer: The conductivity of water depends on the concentration of dissolved ions in solution. ... This is because the Sodium Chloride salt dissociates into ions. Hence sea water is about a million times more conductive than fresh water.
Answer:
Question 1)
a) The speed of the drums is increased from 2 ft/s to 4 ft/s in 4 s. From the below kinematic equations the acceleration of the drums can be determined.
This is the linear acceleration of the drums. Since the tape does not slip on the drums, by the rule of rolling without slipping,
where α is the angular acceleration.
In order to continue this question, the radius of the drums should be given.
Let us denote the radius of the drums as R, the angular acceleration of drum B is
α = 0.5/R.
b) The distance travelled by the drums can be found by the following kinematics formula:
One revolution is equal to the circumference of the drum. So, total number of revolutions is
Question 2)
a) In a rocket propulsion question, the acceleration of the rocket can be found by the following formula:
b) 
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.
