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Lavneesh Rajput
Subject: Physics
, asked on 3/5/18
Q. please derive this equation of discharging current in rc circuit
i
=
E
R
e
-
t
/
R
C
Answer
1
Jeneeta Eliza John
Subject: Physics
, asked on 1/5/18
Q32. The rms value of potential difference V shown in the figure is
(1)
V
0
2
(2)
V
0
3
(3)
V
0
(4)
V
0
2
Answer
1
Jeneeta Eliza John
Subject: Physics
, asked on 1/5/18
Please explain no.23. Answer is (2)
I
n
a
R
-
L
c
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c
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=
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/
τ
,
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t
=
0
t
o
t
=
τ
i
s
(
1
)
2
I
0
e
[
e
-
1
]
(
2
)
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0
e
[
e
-
1
]
(
3
)
2
I
0
e
(
4
)
I
0
e
Answer
2
Jeneeta Eliza John
Subject: Physics
, asked on 1/5/18
An AC source of 25 volt, 60 Hz i applied across C-R series circuit as shown. If voltage across resistnace is 20 volt, then voltage across capacitor is
(1) 20 V
(2) 15 V
(3) 25 V
(4) Cannot be calculated unless value of C is not given
Answer
1
Aparna Sahu
Subject: Physics
, asked on 21/4/18
Solve this:
47.
An an A.C. circuit, the current flowing is i = 5 sin(100t
-
π
2
) amp and the potential difference is V = 200 sin 100t volt. The power consumption is equal to
(a) 1000 W
(b) 40 W
(c) 20 W
(d) 0 W
Answer
1
Aparna Sahu
Subject: Physics
, asked on 19/4/18
10. 22 gm of CO
2
at 27°C mixed with 60 gm of O
2
at 37°C. The temperature of mixture is
(a) 27°C (b) 30.5°C
(c) 32°C (d) 37°C
Answer
2
Aparna Sahu
Subject: Physics
, asked on 18/4/18
T
h
e
e
q
u
a
t
i
o
n
o
f
a
n
A
.
C
.
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s
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d
b
y
V
=
V
0
sin
ω
t
.
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n
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h
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t
t
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f
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m
i
n
i
t
i
a
l
t
i
m
e
t
=
0
.
(
a
)
t
/
12
(
b
)
t
/
8
(
c
)
t
/
6
(
d
)
t
/
4
Answer
2
Laieeqa
Subject: Physics
, asked on 17/4/18
Solve this:
Q9. A plane electromagnetic wave of frequency 20 MHz travels through a space along x direction. If the electric field vector at a certain point in space is 6 V m
–1
, what is the magnetic field vector at that point?
(1) 2 × 10
–8
T (2)
1
2
×
10
-
8
T
(3) 2 T (4)
1
2
T
Answer
1
Aparna Sahu
Subject: Physics
, asked on 16/4/18
38
.
A
t
w
h
a
t
t
e
m
p
r
a
t
u
r
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t
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s
1
.
5
t
i
m
e
s
t
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e
v
e
l
o
c
i
t
y
a
t
7
°
C
?
a
357
°
C
b
476
°
C
c
588
°
C
d
819
°
C
Answer
1
Aparna Sahu
Subject: Physics
, asked on 6/4/18
Solve qus no. 18
Q.18. A carnot engine operates between a sink at temperature 300 K and a source at temperature 11 Kelvin. It takes 200 J of heat from the source and delivers 120 J to sink in a cycle. The temperature of the source is
(a) 400 K
(b) 500 K
(c) 600 K
(d) None
Answer
2
Apurva Inamdar
Subject: Physics
, asked on 29/3/18
Q. A car travels half of its journey with the speed of 30 m/s and next half with speed of v. If average speed pf the car is 24 m/s, then speed of the car in second half is
30 m/s
20 m/s
40 m/s
50 m/s
Answer
2
Apurva Inamdar
Subject: Physics
, asked on 29/3/18
Solve this
:
Please answer the 40
th
question-
40. Acceleration versus time graph of a moving object is given below. Velocity of the object will be at t = 4 second (Initial velocity is zero):
(1) 1 m/s (2) 8 m/s
(3) 4 m/s (4)
1
2
m/s
Answer
1
Apurva Inamdar
Subject: Physics
, asked on 21/3/18
Q. The time period of oscillations of single pendulum is T = 2
π
L
/
g
. L is about 10 cm and known to 1 mm accuracy . The time period of oscillations is about 0.5 s . The time of 100 oscillations is measured with a wrist watch of 1s resolution . What is the accuracy in determination of 'g' ? (1) 1% (2) 3 % (3) 5 % (4) 7 %
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
Q. A voltmeter of '0-50mv' range of resistance 50
Ω
will have to convert with an Ammeter of range
'0- 10A'. How it will be done ? What happens when ammeter is connected in a circuit with parallel ?
Answer
2
Shubhrajyoti Ghosh
Subject: Physics
, asked on 15/3/18
No links please
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v
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l
t
a
g
e
,
e
=
5
sin
2
π
t
+
12
cos
2
π
t
v
o
l
t
s
.
Answer
1
1
2
3
4
5
Next
What are you looking for?
(1) (2)
(3) (4)
(1) 20 V
(2) 15 V
(3) 25 V
(4) Cannot be calculated unless value of C is not given
47. An an A.C. circuit, the current flowing is i = 5 sin(100t ) amp and the potential difference is V = 200 sin 100t volt. The power consumption is equal to
(a) 1000 W
(b) 40 W
(c) 20 W
(d) 0 W
(a) 27°C (b) 30.5°C
(c) 32°C (d) 37°C
Q9. A plane electromagnetic wave of frequency 20 MHz travels through a space along x direction. If the electric field vector at a certain point in space is 6 V m–1, what is the magnetic field vector at that point?
(1) 2 × 10–8 T (2)
(3) 2 T (4)
Q.18. A carnot engine operates between a sink at temperature 300 K and a source at temperature 11 Kelvin. It takes 200 J of heat from the source and delivers 120 J to sink in a cycle. The temperature of the source is
(a) 400 K
(b) 500 K
(c) 600 K
(d) None
40. Acceleration versus time graph of a moving object is given below. Velocity of the object will be at t = 4 second (Initial velocity is zero):
(1) 1 m/s (2) 8 m/s
(3) 4 m/s (4) m/s
'0- 10A'. How it will be done ? What happens when ammeter is connected in a circuit with parallel ?