# Reasonable estimates

#### prudenteyes

Does anyone has the sheet about reasonable estimates??? My sir gave me a sheet where plenty of estimations were given but I sadly lost it. If anybody else has got it please share. I urgently need it!!! Please!

#### workinghard

i posted it already u search da forum!!!

#### prudenteyes

I have just been through the forum and I can not find it. Can you please repost it here? Please???

#### workinghard

oh k...
here it is
1. mass of an apple: 50 – 500g
2. no of joules of energy in 1kWh = 3 – 4 J
3. wavelength of red light in a vacuum = 6 – 8 (x 107) m
4. pressure due to depth of 10m of water = (5x 104) - (5 x 105) Pa
5. speed of sound in air = 100 – 900 m/s
6. density of air at rtp = 0.5 – 1.5 kg/m3
7. mass of a protractor = 5 – 50g
8. volume in cm3 of head of an adult person = 2 – 9 (x 10-3)
9. frequency of audible sound = 20Hz – 20 kHz
10. wavelength in nm of UV = 10 – 400nm
11. mass of a plastic 30cm ruler = 10 – 100g
12. density of air at atm = 0.1 – 10 kg/m3
13. thickness of a sheet of paper = 0.05 – 0.15mm
14. time for sound 2 travel 100m in air = 0.25 – 0.5s
15. weight of 1000cm3 of water = 8 – 12 N
16. mass of an orange = 100 – 150g
17. mass of an adult human = 50 – 100 kg
18. height of a room in a house = 2 – 3m
19. diameter of a pencil = .5 – 1cm
20. volume of a small bean = 0.5cm3
21. volume of a human head = 4 x 10-3m3
22. the speed of a jumbo jet = 220m/s
23. the temperature of a human body = 310K
24. dis. of earth to the sun = 1.5 x 1011m
25. length of a car = 4m
26. diameter of a hair = 5 x 10-4m
27. diameter of an atom = 3 x 10-10m
28. diameter of a nucleus = 6 x 10-15m
29. typical car speed = 22m/s
30. walking speed = 1.5m/s
31. snail’s speed = .001m/s
32. earth around sun speed = 30000m/s
33. acceleration of family car = 2m/s2
34. acc of freefall on moon = 2m/s2
35. energy released from 100kg of coal = 1010J
36. beat of heart energy = 1J
37. burning of a match energy = 1000J
38. sound of speech on ear for 1sec = .001J

• Eesha.N and mahnam

#### prudenteyes

Thank you so much!
Can you or someone else please tell me how many antinodes make one wave length? And how many nodes make one wavelength?

#### princesszahra

prudenteyes said:
Thank you so much!
Can you or someone else please tell me how many antinodes make one wave length? And how many nodes make one wavelength?
3 antinodes=1 wavelength
3nodes=1wavelength!

its 3! sorry!

#### libra94

princesszahra said:
prudenteyes said:
Thank you so much!
Can you or someone else please tell me how many antinodes make one wave length? And how many nodes make one wavelength?
2 antinodes=1 wavelength
2 nodes=1wavelength!
isn't it 3?? :shock:

#### Zenzenzen

workinghard said:
oh k...
here it is
1. mass of an apple: 50 – 500g
2. no of joules of energy in 1kWh = 3 – 4 J
3. wavelength of red light in a vacuum = 6 – 8 (x 107) m
4. pressure due to depth of 10m of water = (5x 104) - (5 x 105) Pa
5. speed of sound in air = 100 – 900 m/s
6. density of air at rtp = 0.5 – 1.5 kg/m3
7. mass of a protractor = 5 – 50g
8. volume in cm3 of head of an adult person = 2 – 9 (x 10-3)
9. frequency of audible sound = 20Hz – 20 kHz
10. wavelength in nm of UV = 10 – 400nm
11. mass of a plastic 30cm ruler = 10 – 100g
12. density of air at atm = 0.1 – 10 kg/m3
13. thickness of a sheet of paper = 0.05 – 0.15mm
14. time for sound 2 travel 100m in air = 0.25 – 0.5s
15. weight of 1000cm3 of water = 8 – 12 N
16. mass of an orange = 100 – 150g
17. mass of an adult human = 50 – 100 kg
18. height of a room in a house = 2 – 3m
19. diameter of a pencil = .5 – 1cm
20. volume of a small bean = 0.5cm3
21. volume of a human head = 4 x 10-3m3
22. the speed of a jumbo jet = 220m/s
23. the temperature of a human body = 310K
24. dis. of earth to the sun = 1.5 x 1011m
25. length of a car = 4m
26. diameter of a hair = 5 x 10-4m
27. diameter of an atom = 3 x 10-10m
28. diameter of a nucleus = 6 x 10-15m
29. typical car speed = 22m/s
30. walking speed = 1.5m/s
31. snail’s speed = .001m/s
32. earth around sun speed = 30000m/s
33. acceleration of family car = 2m/s2
34. acc of freefall on moon = 2m/s2
35. energy released from 100kg of coal = 1010J
36. beat of heart energy = 1J
37. burning of a match energy = 1000J
38. sound of speech on ear for 1sec = .001J
I think energy released from 100kg of coal is much more than 1010 J, as seeing that a match releases 1000J O_O

#### workinghard

its 10 ^10
i wrote in ms word format with powers
n here it changed sorry :sorry: