u= 215 km/hr = 215 * 1000/ 3600 = aprx 60m/s
v=0
t=2.7sec
v= u - at
u= at
60/2.7 = 22.23 m/s^2
Hope it helps
v = v₀ + at
v = final speed, v₀ = initial speed, a = acceleration, t = elapsed time
Given values:
v₀ = 0m/s (starts from rest), a = 9.81m/s², t = 3s
Plug in and solve for v:
v = 0 + 9.81(3)
v = 29.4m/s
The answer would be a.
a chemical change is a change to the chemical makeup of a substance so if the bonds are unchanged it would be a characteristic of a physical change
Answer:
6.0 ×
W/![m^{2}](https://tex.z-dn.net/?f=m%5E%7B2%7D)
Explanation:
From Wien's displacement formula;
Q = e A![T^{4}](https://tex.z-dn.net/?f=T%5E%7B4%7D)
Where: Q is the quantity of heat transferred, e is the emissivity of the surface, A is the area, and T is the temperature.
The emissive intensity =
= e![T^{4}](https://tex.z-dn.net/?f=T%5E%7B4%7D)
Given from the question that: e = 0.6 and T = 1000K, thus;
emissive intensity = 0.6 × ![(1000)^{4}](https://tex.z-dn.net/?f=%281000%29%5E%7B4%7D)
= 0.6 × 1.0 × ![10^{12}](https://tex.z-dn.net/?f=10%5E%7B12%7D)
= 6.0 ×
![\frac{W}{m^{2} }](https://tex.z-dn.net/?f=%5Cfrac%7BW%7D%7Bm%5E%7B2%7D%20%7D)
Therefore, the emissive intensity coming out of the surface is 6.0 ×
W/
.
PEg = Mass x Height x Gravity. So it doesn't matter how much PEg she started with, since you're finding how much it changed when she walked down 2.5 meters of stairs. So by plugging into the equation, you'll find how much potential energy was lost by walking down. (I'll leave it up to you since idk if you use 10 or 9.8 as gravity)