Part A
Free fall motion
h = 3.1 m
Equation: Vf = √(2gh) = √(2*9.8 m/s^2 * 3.1 m) = 7.8 m/s
That is the only part in the question.
Answer:
Bulb 1 has more resistance.
Explanation:
Given that,
Two lightbulbs work on a 120-V circuit.
The power of circuit 1, P₁ = 50 W
The power of circuit 2, P₂ = 100 W
We need to find the bulb that has a higher resistance.
The power of the bulb is given by :
![P = \dfrac{V^2}{R}](https://tex.z-dn.net/?f=P%20%3D%20%5Cdfrac%7BV%5E2%7D%7BR%7D)
For bulb 1,
![R_1=\dfrac{V^2}{P_1}\\\\R_1=\dfrac{(120)^2}{50}\\\\R_1=288\ \Omega](https://tex.z-dn.net/?f=R_1%3D%5Cdfrac%7BV%5E2%7D%7BP_1%7D%5C%5C%5C%5CR_1%3D%5Cdfrac%7B%28120%29%5E2%7D%7B50%7D%5C%5C%5C%5CR_1%3D288%5C%20%5COmega)
For bulb 2,
![R_2=\dfrac{V^2}{P_2}\\\\R_2=\dfrac{(120)^2}{100}\\\\R_2=144\ \Omega](https://tex.z-dn.net/?f=R_2%3D%5Cdfrac%7BV%5E2%7D%7BP_2%7D%5C%5C%5C%5CR_2%3D%5Cdfrac%7B%28120%29%5E2%7D%7B100%7D%5C%5C%5C%5CR_2%3D144%5C%20%5COmega)
So, bulb 1 has higher resistance.
Answer:
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance.
A bell or a siren or a ring in somewhere
Answer:
"where crests and troughs have their maxima at the same time"
Crests and troughs are 180 deg out of phase and when they have their maxima at the same time and place, their net contribution will be zero"