Answer:
a) 
= 928 J
, b)U = -62.7 J
, c) K = 0
, d) Y = 11.0367 m, e) v = 15.23 m / s
Explanation:
To solve this exercise we will use the concepts of mechanical energy.
a) The elastic potential energy is
= ½ k x²
= ½ 2900 0.80²
= 928 J
b) place the origin at the point of the uncompressed spring, the spider's potential energy
U = m h and
U = 8 9.8 (-0.80)
U = -62.7 J
c) Before releasing the spring the spider is still, so its true speed and therefore the kinetic energy also
K = ½ m v²
K = 0
d) write the energy at two points, maximum compression and maximum height
Em₀ = ke = ½ m x²
= mg y
Emo =
½ k x² = m g y
y = ½ k x² / m g
y = ½ 2900 0.8² / (8 9.8)
y = 11.8367 m
As zero was placed for the spring without stretching the height from that reference is
Y = y- 0.80
Y = 11.8367 -0.80
Y = 11.0367 m
Bonus
Energy for maximum compression and uncompressed spring
Emo = ½ k x² = 928 J
= ½ m v²
Emo =
Emo = ½ m v²
v =√ 2Emo / m
v = √ (2 928/8)
v = 15.23 m / s
Answer:
1 kg lead to earth is greater attraction as mass of earth is much more than 1kg lead.
Explanation:
Objects with more mass have more gravity. Gravity also gets weaker with distance. So, the closer objects are to each other, the stronger their gravitational pull is. Earth's gravity comes from all its mass
Answer: Kinetic energy
Explanation:
Kinetic energy and potential energy can change forms. For example, the car moving up the hill is kinetic energy
Illluminance is the measurement of photo-metric power. That means, illuminance is the rate of photo-metric flux that is received by a surface per area. It is usually expressed as a unit of W/m^2. Thus, from the choices, the answer we're looking for is illuminance.
I would say the atmosphere because air and oxygen are essential for human life however it is debatable. You should check out this prezi and judge for yourself which sphere is effected the most from forest fires based on the descriptions on how a forest fire effects all four spheres.
https://prezi.com/m/50ogw-qsyoxc/the-four-spheres/
