Explanation:
Given parameters:
Initial velocity = 72km/hr
Final velocity = 0km/hr
Time taken = 25s
Unknown:
Acceleration = ?
Solution:
To solve this problem, convert km/hr to m/s;
1000m = 1km
3600s = 1hr
72km/hr;
1km/hr = 0.278m/s
72km/hr = 0.278 x 72 = 20.02m/s
Acceleration is the change in velocity divided by the time taken;
Acceleration =
Acceleration =
= -0.8m/s
The car is actually decelerating at a rate of 0.8m/s
<span>E=hc/wav. len
E = (6.62 x 10^-34 x 3 x 10^8)/0.0275 x 10^-9
E = 7.22182 x 10^-15 J
To convert to eV divide by 1.6 x 10^-19
E = 7.22182 x 10^-15/1.6 x 10^-19 eV
E =45.36 x 10^3 eV
Th energy, E, of a single x-ray photon in eV is = 45.36keV.
Number of photons, n = total energy/ energy of photon
n = 3.85 x 10^-6/7.22182 x 10^-15
n = 5.33 x 10^8 photons </span>
Answer:
The answer should be <u>WORK </u>
<em>(Hope this Helps)</em>
Explanation:
work is equal to the product of force and distance.
W=F*S
W=Work
F=Force applied
S=Distance
Answer : The mass of a sample of water is, 888.89 grams
Explanation :
Latent heat of vaporization : It is defined as the amount of heat energy released or absorbed when the liquid converted to vapor at atmospheric pressure at its boiling point.
Formula used :
![q=L\times m](https://tex.z-dn.net/?f=q%3DL%5Ctimes%20m)
where,
q = heat = 2000 kJ =
(1 kJ = 1000 J)
L = latent heat of vaporization of water = ![2.25\times 10^6J/kg](https://tex.z-dn.net/?f=2.25%5Ctimes%2010%5E6J%2Fkg)
m = mass of sample of water = ?
Now put all the given values in the above formula, we get:
![2\times 10^6J=(2.25\times 10^6J/kg)\times m](https://tex.z-dn.net/?f=2%5Ctimes%2010%5E6J%3D%282.25%5Ctimes%2010%5E6J%2Fkg%29%5Ctimes%20m)
(1 kg = 1000 g)
Therefore, the mass of a sample of water is, 888.89 grams