The particle has a constant horizontal velocity, and a vertical force won't affect the horizontal speed, so it should be fairly easy to find the last part, "the time taken for a 10m horizontal displacement," using a kinematic equation.
X = x + vt + (1/2)at²
10 = 0 + (1.6)t + (1/2)(0)t²
10/1.6 = t
t = 6.25s
So now we have to find the vertical displacement over 6.25 seconds on a particle of a 2.5kg mass with a force of 8N.
Start with Newton's second law.
F = ma
8 = (2.5)a
a = 3.2m/s²
Now, use kinematics again.
Y = y + vt + (1/2)at²
Y = 0 + (0)(6.25) + (1/2)(3.2)(6.25)²
Y = <u>62.5m</u>
Answer: 1.77 m/s²
Explanation: acceleration is expressed in:
a= ∆v / t = vf-vi/t
a= 18.8 m/s - 0 / 10.6 s
a= 1.77 m/s²
A descriptive observation may very well be a mixture of both quantitative and qualitative as it can utilize elements of both types. Qualitative deals with the kinds of observations that cannot be measured in numerical form. Quantitative data is just that.
Both the answers from "Big D" and "N9KXF" are correct, but not complete. There is one aspect that needs to be remembered for AC power - the phase relationship between the voltage and current.
<span>For AC power, the more complete equation for power is P = V * I * cosx, where x is the phase angle between voltage and current. </span>
<span>If the phase angle between voltage and current is 90 degrees, then even though current may be flowing, the total power over a cycle would be zero. Reactive elements like inductors and capacitors have a 90degree phase relationship between voltage and current. They do not "dissipate" energy. They store energy and give it back during different parts of the AC cycle. </span>