Answer:
Electrical
Explanation:
She uses a battery, which is electrical.
It doesn't operate using chemicals, heat, or light
Explanation:
The compass needle moved when the wire was connected to the battery. The important point here is that the needle is affected by the wire only when both ends of the wire are connected to the battery because only at this time is current flowing through the circuit.
The article is not found here but surveys are important because they are representative samples of a population.
<h3>What is a survey?</h3>
A survey is a useful tool based on population samples, which is used to make statistical analyses in a given investigation.
Differences in surveys are generally due to small sample sizes, which may lead to errors in the analysis of data.
In conclusion, the article is not found here but surveys are important because they are representative samples of a population.
Learn more about surveys here:
brainly.com/question/13624055
#SPJ1
Answer:
V1 =8.1 m/s
Explanation:
height at highest point (h2) = 4.1 m
height at lowest point (h1) = 0.8 m
acceleration due to gravity (g) = 9.8 m/s^{2}
from conservation of energy, the total energy at the lowest point will be the same as the total energy at the highest point. therefore
mgh1 +
= mgh2 + 
where
- speed at highest point = V2
- speed at lowest point = V1
- mass of the girl and swing = m
- at the highest point, the speed is minimum (V1 = 0)
- at the lowest point the speed is maximum (V2 is the maximum speed)
- therefore the equation becomes mgh1 +
= mgh2
m(gh1 +
) = m(gh2)
gh1 +
= gh2
V1 = 
now we can substitute all required values into the equation above.
V1 = 
V1 = 
V1 =8.1 m/s
C standards are based on observable, reproducible natural phenomena.