We don't even need to know how many pulses were produced
in those 3 seconds.
The beginning of the first pulse took 3 seconds to travel
45 centimeters from the generator.
Its speed is (45 cm) / (3 sec) = 15 cm/sec.
Answer:
A) being influenced by equal amounts of gravity and air resistance.
Explanation:
B) slowing down because of an unbalanced force of air resistance.
False - if it was slowing down, then the velocity would go down.
D) on the ground and is not falling anymore.
False - This would be mistaken as the answer but it is not because if the person is not falling anymore the horizontal line should be at the x-axis, meaning that there is no more velocity.
C) accelerating because of an unbalanced force of gravity.
False - The line would otherwise be going up or down.
The 1st quadrant (0-90 degrees) is the only quadrant where none of the components are negative, so that means that any angle larger than 90 degrees will result in one of the components being negative.
Presume we are looking for the current:
V = IR
120 = I*360
120/360 = I
1/3 = I
I = 1/3 = 0.333..
Current ≈ 0.33 Ampere.