A moving roller coaster speeds up with constant acceleration for 2.3s until it reaches a velocity of 35m/s. During this time, th
e roller coaster travels 41m. We want to find the initial velocity of the roller coaster before it starts to accelerate. Which kinematic formula would be most useful to solve for the target unknown?
1 answer:
You might be interested in
Answer: a) 1 b) 61 W c) 61 W
Explanation:
a) The Power Factor (also known as cos φ), is defined by the difference in phase between current and voltage, in a RLC series circuit, and is expressed as follows:
cos φ = R / Z = R /
In resonance, XL =XC, so the circuit behaves like it were purely resistive, so Z=R.
Replacing in the expression for power factor, we have:
cos φ = R/Z = R/R = 1
This means that in resonance, current and voltage are in phase each other.
b) The average power delivered by the source, in resonance, is simply the power dissipated at the resistance R, as follows:
Pavg = V² rms / R = V₀² / √2 / R = 61 W
c) If the circuit remains in resonance, the average power , which does not depends on frequency provided this condition remains, keeps the same, i.e. , 61 W.