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| From: haroonaman | Reply 61 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 41 |
The speed of light in glass increases with the increase in the wavelength of
light.
Posted at: Fri Feb 12 04:53:50 2010 (GMT)
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| From: haroonaman | Reply 62 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 43 |
Refractive index of water = Real Depth / Apparent Depth .
Posted at: Fri Feb 12 05:28:31 2010 (GMT)
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| From: haroonaman | Reply 63 of 141 | Reply | View replies (3)
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| Subject: Contributed Answer/Explanation to Q. 44 |
The distance is :
Given ,
t = 3 sec
Let d m be the distance.
For 1st Echo,
2d / V = 3
After moving 82.5m closer to the cliff, for second echo , 2(d - 82.5) / V
= 2.5
d / d- 82.5 = 3 / 2.5d = 3d - 247.5 or 0.5 d = 247.5
.
...
d = 495 m
Velocity of light = 2d / 3 = 2 x 495 = 330 ms-1
3
Posted at: Fri Feb 12 05:41:24 2010 (GMT)
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| From: haroonaman | Reply 64 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 44 |
The distance is :
Given ,
t = 3 sec
Let d m be the distance.
For 1st Echo,
2d / V = 3
After moving 82.5m closer to the cliff, for second echo , 2(d - 82.5) / V
= 2.5
d / d- 82.5 = 3 / 2.5d = 3d - 247.5 or 0.5 d = 247.5
.
...
d = 495 m
Velocity of Sound = 2d / 3 = 2 x 495 = 330 ms-1
3
Posted at: Fri Feb 12 05:41:48 2010 (GMT)
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| From: haroonaman | Reply 65 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 44 |
The distance is :
Given ,
t = 3 sec
Let d m be the distance.
For 1st Echo,
2d / V = 3
After moving 82.5m closer to the cliff, for second echo , 2(d - 82.5) / V
= 2.5
d / d- 82.5 = 3 / 2.5d = 3d - 247.5 or 0.5 d = 247.5
.
...
d = 495 m
Velocity of Sound = 2d / 3 = 2 x 495 = 330 ms-1
3
Posted at: Fri Feb 12 05:43:55 2010 (GMT)
|
| From: haroonaman | Reply 66 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 44 |
The distance is :
Given ,
t = 3 sec
Let d m be the distance.
For 1st Echo,
2d / V = 3
After moving 82.5m closer to the cliff, for second echo , 2(d - 82.5) / V
= 2.5
d / d- 82.5 = 3 / 2.5d = 3d - 247.5 or 0.5 d = 247.5
.
...
d = 495 m
Velocity of Sound = 2d / 3 = 2 x 495 = 330 ms-1
3
Posted at: Fri Feb 12 05:44:14 2010 (GMT)
|
| From: haroonaman | Reply 67 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 45 |
velocity is =
Velocity of Sound = 2d = 2 x 495 = 330 ms-1
3
3
Posted at: Fri Feb 12 05:46:14 2010 (GMT)
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| From: haroonaman | Reply 68 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 46 |
Specific heat capacity of a substance is the quantity of heat required to
raise temperature of 1kg of that substance by 1 degree C.
Posted at: Fri Feb 12 05:50:41 2010 (GMT)
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| From: haroonaman | Reply 69 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 47 |
The heat supplied to a substance during its change of state dous not cause
any rise in temperature as this heat is used up in increasing the internal
potential energy .
Posted at: Fri Feb 12 06:01:42 2010 (GMT)
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| From: haroonaman | Reply 70 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 48 |
Mass of the substance
Q = m x c x t
800 = m x 500 x 80
m = 800
500 x 80
= 0.02 kg.
Posted at: Fri Feb 12 07:22:53 2010 (GMT)
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| From: haroonaman | Reply 71 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 49 |
the specific latent heat of fusion
Q = m x L
800 = 0.02 x L
L = 800
0.02
L = 40000 J kg-1
Posted at: Fri Feb 12 07:28:21 2010 (GMT)
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| From: haroonaman | Reply 72 of 141 | Reply | View replies (2)
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| Subject: Contributed Answer/Explanation to Q. 50 |
Earthing of an electrical appliance means connecting the earth wire of cable
to the outer metal case of an appliance.
Posted at: Fri Feb 12 07:30:24 2010 (GMT)
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| From: haroonaman | Reply 73 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 50 |
Earthing of an electrical appliance means connecting the earth wire of cable
to the outer metal case of an appliance. In case the live wire comes in
contact with the metal case then the heavy current is transmitted to the
earth and prevents shocks./
Posted at: Fri Feb 12 07:32:28 2010 (GMT)
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| From: haroonaman | Reply 74 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 50 |
Earthing of an electrical appliance means connecting the earth wire of cable
to the outer metal case of an appliance. In case the live wire comes in
contact with the metal case then the heavy current is transmitted to the
earth and prevents shocks.
Posted at: Fri Feb 12 07:32:53 2010 (GMT)
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| From: haroonaman | Reply 75 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 51 |
If instead of a direct current an alternating current is used, the soft iron
core does not get magnetised and hence the bell does not ring.
Posted at: Fri Feb 12 07:36:04 2010 (GMT)
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| From: haroonaman | Reply 76 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 52 |
Two factors on which the strength of an induced current depends on are :
(i) Change in amount of magnetic flux.
(ii) Time in which the magnetic flux changes.
Posted at: Fri Feb 12 07:39:57 2010 (GMT)
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| From: haroonaman | Reply 77 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 53 |
When a solenoid that is carrying current is freely suspended it behaves
like a bar magnet and hence rests in the north - south direction.
Posted at: Fri Feb 12 07:43:27 2010 (GMT)
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| From: haroonaman | Reply 78 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 54 |
Current is =
Given,
v = 1.5 V
r = 1 ohm
R = 4 ohm, 20 ohm
Total resistence = 4 + 20 + 1
= 25 ohm
V = RI
1.5 = 25 x I
I = 1.5
25
I = 0.6 A
Posted at: Fri Feb 12 09:52:47 2010 (GMT)
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| From: haroonaman | Reply 79 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 55 |
Potential difference is =
Given,
R = 4.0 ohm
I = 0.6 A
V = RI
... V = 4.0 x 0.6
Potential Difference = 2.4 V
Posted at: Fri Feb 12 09:58:21 2010 (GMT)
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| From: haroonaman | Reply 80 of 141 | Reply | |
| Subject: Contributed Answer/Explanation to Q. 56 |
Voltage drop :
Gi
ven,
I = 0.6 A
r = 1 ohm
V = I x r
... Voltage drop = 0.6 V
Posted at: Fri Feb 12 10:02:02 2010 (GMT)
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