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Khyati
Subject: Physics
, asked on 28/3/18
A person having mass 60kg is standing on a stationary raft in a river. The mass of raft is 40kg. The distance between person and bank is 30m . The person niw starts running towards the bank with velocity of 10mpersec. How far will the person be from the bank after one second.
Answer
1
Devjeet
Subject: Physics
, asked on 25/3/18
mv
'
2
r
>
mg
cos
θ
Why is the answer not option c ? Can you please solve and explain properly?:
2. For vertical circular motion if v
lowermost
point
<
5
r
g
. then
(a) the rope will slack T=mg cos
θ
(b) the rope will slack
mv
'
2
r
<
mg
cos
θ
(c) the rope will slack
mv
'
2
r
>
mg
cos
θ
(d) rope will leave the circular path at the very next moment when mv'
2
mv
'
2
r
=
mg
cos
θ
Answer
1
Divya Mahesh
Subject: Physics
, asked on 24/3/18
↵
Please
explain and give reason.
39
A truck and a car are with Velocity v
towards each other. They collide head in and
Stops after Some time. If the time Of collision is 1s.
which vehicle will have maximum in change in momentum?
(1) car
(2) truck
(3) Both will have same
(4) None of these
Answer
1
Divya Mahesh
Subject: Physics
, asked on 24/3/18
Find the value of T. Solve it.
T
-
3
x
9
.
8
=
3
a
-
-
-
-
(
1
)
T
-
7
x
9
.
8
=
7
a
-
-
-
-
-
(
2
)
Answer
1
Divya Mahesh
Subject: Physics
, asked on 23/3/18
A
b
o
d
y
i
s
a
m
d
e
i
n
t
h
e
f
o
r
m
o
f
w
e
d
g
e
w
i
t
h
a
n
a
n
g
l
e
45
∘
.
S
e
e
f
i
g
u
r
e
.
A
b
a
l
l
o
f
m
a
s
s
m
,
m
o
v
i
n
g
h
o
r
i
z
o
n
t
a
l
l
y
a
t
a
s
p
e
e
d
v
0
=
2
m
/
s
,
c
o
l
l
i
d
e
s
w
i
t
h
t
h
e
w
e
d
g
e
o
f
m
a
s
s
M
=
2
m
.
A
s
a
r
e
s
u
l
t
o
f
t
h
e
i
m
p
a
c
t
,
t
h
e
b
a
l
l
b
o
u
n
c
e
s
v
e
r
t
i
c
a
l
l
y
u
p
w
a
r
d
.
N
e
g
l
e
c
t
t
h
e
f
r
i
c
t
i
o
n
b
e
t
w
e
e
n
t
h
e
w
e
d
g
e
a
n
d
h
o
r
i
z
o
n
t
a
l
s
u
r
f
a
c
e
.
T
h
e
s
p
e
e
d
o
f
t
h
e
b
a
l
l
j
u
s
t
a
f
t
e
r
t
h
e
i
m
p
a
c
t
i
s
(
1
)
0
.
5
m
/
s
(
2
)
2
m
/
s
(
3
)
2
m
/
s
(
4
)
1
m
/
s
Answer
1
Divya Mahesh
Subject: Physics
, asked on 23/3/18
Solve this.
Answer
1
Divya Mahesh
Subject: Physics
, asked on 23/3/18
A
sin
g
l
e
h
o
r
i
z
o
n
t
a
l
f
o
r
c
e
F
i
s
a
p
p
l
i
e
d
t
o
a
b
l
o
c
k
o
f
m
a
s
s
M
1
,
w
h
i
c
h
i
s
i
n
c
o
n
t
a
c
t
w
i
t
h
a
n
o
t
h
e
r
b
l
o
c
k
o
f
m
a
s
s
M
2
a
s
s
h
o
w
n
i
n
t
h
e
f
i
g
u
r
e
.
I
f
t
h
e
s
u
r
f
a
c
e
s
a
r
e
f
r
i
c
t
i
o
n
l
e
s
s
,
t
h
e
f
o
r
c
e
b
e
t
w
e
e
n
t
h
e
b
l
o
c
k
i
s
(
1
)
M
1
F
M
2
(
2
)
M
1
F
M
1
+
M
2
(
3
)
M
2
F
M
1
+
M
2
(
4
)
M
2
F
M
1
Answer
1
Divya Mahesh
Subject: Physics
, asked on 23/3/18
T
w
o
b
o
d
i
e
s
o
f
m
a
s
s
e
s
m
a
n
d
3
m
,
m
o
v
i
n
g
w
i
t
h
v
e
l
o
c
i
t
i
e
s
3
v
a
n
d
v
r
e
s
p
e
c
t
i
v
e
l
y
a
l
o
n
g
s
a
m
e
d
i
r
e
c
t
i
o
n
,
c
o
l
l
i
d
e
w
i
t
h
e
a
c
h
o
t
h
e
r
.
A
f
t
e
r
c
o
l
l
i
s
i
o
n
t
h
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y
s
t
i
c
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t
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t
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r
a
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d
m
o
v
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w
i
t
h
a
v
e
l
o
c
i
t
y
V
i
n
t
h
e
s
a
m
e
d
i
r
e
c
t
i
o
n
.
T
h
e
n
(
1
)
V
=
v
(
2
)
V
=
3
2
v
(
3
)
V
=
2
v
(
4
)
V
=
4
3
v
Answer
1
Erw Trjerth
Subject: Physics
, asked on 18/3/18
Q What is the safe maximum speed of a car on a level road taking a sharp circular turn of radius 4 m without reducing the speed , if coefficient of static friction between the tyre and road is 0.1
Answer
1
Priyanshi
Subject: Physics
, asked on 12/3/18
Q 36. A boy of mass m standing on a block of mass M which in turn lying on a rough surface of coefficient of static friction
μ
. Boy is pulling him through pulley system shown in figure .The maximum Force he can exert that block does not slip:
(
A
)
m
M
+
m
g
(
B
)
μ
mM
M
+
m
g
(
C
)
μ
M
+
m
1
+
μ
g
(
D
)
μ
M
-
m
1
-
μ
g
Answer
2
Aishwarya
Subject: Physics
, asked on 11/3/18
a car wheel are 1.5 m apart has it centre of gravity 0 .75 m above the ground calculate the maximum speed at which it can go round and unbancked curved road of radius 20 m.?
Answer
2
Sonali Hensh
Subject: Physics
, asked on 10/3/18
A. Body oscillates with simple harmonic motion according to the equation x ( t) = 5 cos(2? t + ?/4)
Where x is in metres and t is in seconds. Calculate the following:
A). Displacement at t= o
B) angular frequency
C). Magnitude of velocity ( maximum)
Answer
1
Naga Nandhini
Subject: Physics
, asked on 9/3/18
Do answer this!
23
Past month, a group of friends went for a jungle safari. They wanted to see the tiger
in the jungle. They were told that tiger comes out at night for his food and in early
morning to drink water. So, they put their tents near the river. In the night, one of the
friends. Aman who could not sleep started walking around the camp. Suddenly, he
saw a tiger at some distance. He was both afraid and excited. He started moving
back to call his friends but suddenly, the tiger jumped towards Aman and he
shouted for help. Hearing his voice, one of his friends came out with a gun and fired
some shots which stopped the tiger in his tracks and fortunately, Aman was saved.
(i) Aman should not have moved out alone in night justify. [1]
(ii) If the man that can fire 50 g bullet with d velocity of 150 m/s. A 60 kg tiger
springs at him with a velocity of 10 ms
-l
. How many bullets must the man fire
per second in order to stop the tiger in his track? [2]
(iii) Explain the reason for recoiling of gun. [1]
Answer
2
Sarthak Manojkumar Jaiswal
Subject: Physics
, asked on 9/3/18
A plano-convex lens acts like a concave mirror of 28 cm focal length when its plane surface is silvered and like a concave mirror of 10 cm focal length when its curved surface is silvered. What is the refractive index of the material of the lens?
Answer
1
Madhura Mandal
Subject: Physics
, asked on 7/3/18
A ladder of length 3 m weighing 20Kg leans on a frictionless wall. Its feet is 1 m from the wall. Find the reaction forces on the wall and the floor.
Answer
2
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What are you looking for?
2. For vertical circular motion if vlowermost point<. then
(a) the rope will slack T=mg cos
(b) the rope will slack
(c) the rope will slack
(d) rope will leave the circular path at the very next moment when mv'2
39 A truck and a car are with Velocity v
towards each other. They collide head in and
Stops after Some time. If the time Of collision is 1s.
which vehicle will have maximum in change in momentum?
(1) car
(2) truck
(3) Both will have same
(4) None of these
Where x is in metres and t is in seconds. Calculate the following:
A). Displacement at t= o
B) angular frequency
C). Magnitude of velocity ( maximum)
23 Past month, a group of friends went for a jungle safari. They wanted to see the tiger
in the jungle. They were told that tiger comes out at night for his food and in early
morning to drink water. So, they put their tents near the river. In the night, one of the
friends. Aman who could not sleep started walking around the camp. Suddenly, he
saw a tiger at some distance. He was both afraid and excited. He started moving
back to call his friends but suddenly, the tiger jumped towards Aman and he
shouted for help. Hearing his voice, one of his friends came out with a gun and fired
some shots which stopped the tiger in his tracks and fortunately, Aman was saved.
(i) Aman should not have moved out alone in night justify. [1]
(ii) If the man that can fire 50 g bullet with d velocity of 150 m/s. A 60 kg tiger
springs at him with a velocity of 10 ms-l. How many bullets must the man fire
per second in order to stop the tiger in his track? [2]
(iii) Explain the reason for recoiling of gun. [1]