Answer:
Yes, ultraviolet light can turn a rubber into solid due to prolong exposure.
Explanation:
A rubber is a material with an elastic property, causing it to be deform by an external force but takes its shape when the force is removed. Light is an electromagnetic wave which causes the sensation of vision. It transfers energy to a medium during propagation through the medium.
Generally, most light do not cause hardness of a rubber. But an ultraviolet light can cause rubber to become solid over a period of time. This is possible if there is a prolong exposure of the rubber, and because of the evaporation of volatiles in the polymer material. Ultraviolet light are known to cause a rubber to become solid.
Answer:
The change in gravitational potential energy of the hiker = 2869685 J
Explanation:
Potential Energy: This is the energy possessed by a body, due to its change in position in the gravitational field. The unit of potential energy is Joules (J)
From the question,
Change in gravitational potential energy = Energy of the hiker at the top of Mt. Whitney - Energy of the hiker at the floor of Death valley.
ΔEp = mgh₂ - mgh₁
ΔEp = mg(h₂-h₁)........................... Equation 1
Where ΔEp = change in Potential Energy of the hiker, m = mass of the hiker, g = acceleration due to gravity, h₁ = lowest point in Death valley, h₂ = Elevation of Mt. Whitney.
Given: m = 65.0 kg, h₁ = -85 m ( because is a valley), h₂ = 4420 m,
Constant: g = 9.8 m/s²
Note: The h₁ is negative because is below sea level.
Substituting into equation 1
ΔEp = 65×9.8×[4420-(-85)]
ΔEp = 637(4420+85)
ΔEp = 637(4505)
ΔEp = 2869685
ΔEp = 2869685 J.
Thus the change in gravitational potential energy of the hiker = 2869685 J
Answer: His average speed in mph over the last 400 m is 7.7 m/s.
Explanation:
Given: Hicham El Guerrouj of Morocco holds the world record in the 1500 m running race. He ran the final 400 m in a time of 51.9 s.
We know that , speed = 
Here , distance = 400m and time = 51.9 s
Then, speed = 
Hence, his average speed in mph over the last 400 m is 7.7 m/s.
PLS help ASAP I DONT have time to answer this, it also detects if it’s right or wrong.
Answer:

Explanation:
The intensity of a star noticed at a certain distance is inversely proportional to the square of distance. Then:

The intensity of the Sun in Jupiter relative to Earth is:


