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Jeneeta Eliza John
Subject: Physics
, asked on 2/5/18
Explain qno.1. Ans(1):
1. A frame is formed by the two uniform identical rods of mass
m
and length
l
as shown in figure.
What will be the co-ordinates at centre of mass ?
1
l
4
,
l
4
2
l
2
,
l
2
3
3
l
4
,
3
l
4
4
5
l
12
,
5
l
12
Answer
0
Raj Aryan
Subject: Physics
, asked on 23/4/18
Q 6
. Three identical rods, each of length l, are joined to form a rigid equilateral triangle. Its radius of gyration about an axis passing through a corner and perpendicular to the plane of the triangle is
A
l
2
B
3
2
l
C
l
2
D
l
3
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
Solve this :
8.
A square plate of mass 10 kg and side 20 m is moving along the groove with the help of two ideal rollers (massless), connected at the corners A and B of the square, as shown in the figure. At a certain moment of time, during motion the corner A is moving with velocity 16 m/s downward. Find the speed of corner D.
(A) 32 m/s (B) 16 m/s
(C) 8 m/s (D) none
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
Solve this :
9. A uniform cylinder rolls from rest down the side of a trough given by y = x
2
. The cylinder does not slip from A to B but the surface of the through is frictionless from B to C as shown. If the cylinder ascends up to C, then (Neglect the radius of cylinder).
(
a
)
y
2
=
y
1
(
b
)
y
2
=
2
3
y
1
(
c
)
y
2
=
y
1
3
(
d
)
y
2
=
2
5
y
1
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
Solve this:
Q.15. A rod of mass m and length 2R can rotate about an axis passing through O in vertical plane. A disc of mass m and radius R is hinged to the other end P of the rod and can freely rotate about P. When disc is at lowest point both rod and disc has angular velocity
ω
. If rod rotates by maximum angle
θ
=
60
°
with downward vertical, then find
ω
in terms of R and g. (all hinges are smooth)
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
Solve this:
Q.14. Three identical cylinders of radius R are in contact. Each cylinder is rotating with angular velocity
ω
. A thin belt is moving without sliding on the cylinders. Calculate the magnitude of velocity of point P with respect to Q. P and Q are two points of belt which are in contact with the cylinder.
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
Solve this:
Q.13. A rod of length l is standing vertically frictionless surface. It is disturbed slightly from this position. Let
ω
a
n
d
α
be the angular speed and angular acceleration of the rod, when the rod turns through an angle
θ
with the vertical, then find the value of acceleration of centre of mass of the rod.
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
12. Two thin planks are moving on a four identical cylinder as shown. There is no slipping at any contact points. Calculate the ratio of angular speed of upper cylinder to lower cylinder.
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
Plz don't give the link for the solution as solution provided is wrong and i would be glad if u help me in this!
Answer
1
Raj Aryan
Subject: Physics
, asked on 23/4/18
A and C are the correct answer. Pls explain how!
Q3. A uniform rod of length
l
and mass 2m rests on a smooth horizontal table. A point of mass m moving horizontally at right angle to the rod with velocity v collides with one end of the rod and sticks to it, then:
(A) angular velocity of the system after collision is v/
l
(B) angular velocity of the system after collision is v/ 2
l
(C) the loss in kinetic energy of the system as a whole as a result of the collision is mv
2
/6
(D) the loss in Kinetic energy of the system as a whole as a result of the collision is 7mv
2
/ 24
Answer
1
Raj Aryan
Subject: Physics
, asked on 19/4/18
Solve this:
2. A T-shaped object with dimensions shown in the figure, is lying on a smooth floor. A force
F
→
is applied at the point P parallel to AB, such that the object has only the translational motion without rotation. Find the location of P with respect to C.
Answer
1
Raj Aryan
Subject: Physics
, asked on 19/4/18
Solve this:
Q3. A bead of mass m sides on a hemispherical surface with a velocity v at an angular position
θ
. If the coefficient of friction between the bead and hemispherical surface is
μ
, Find the magnitude of Angular momentum of bead about O in the position shown.
Answer
1
Raj Aryan
Subject: Physics
, asked on 19/4/18
Solve please?
9. A uniform sphere of radius r starts rolling down without slipping from the top of another fixed sphere of radius R shown in the figure. Find the angular velocity of sphere of radius r at the instant when it leaves contact with the surface of the fixed sphere.
Answer
1
Hermoine
Subject: Physics
, asked on 14/4/18
Two small bodies of masses' and '2m' are placed in a fixed smooth horizontal circular hollow tube of mean radius 'r' as shown. The mass 'm' is moving with speed 'u' and the mass '2m' is stationary. After their first collision, the time elapsed for next collision is : [ coefficient of restitution e = 1/2 ] 2pie r/u 4 pie r/u 3 pie r /u 12 pie r /u
Answer
1
Raj Aryan
Subject: Physics
, asked on 12/4/18
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(
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.
Answer
1
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What are you looking for?
1. A frame is formed by the two uniform identical rods of mass m and length l as shown in figure.
What will be the co-ordinates at centre of mass ?
8. A square plate of mass 10 kg and side 20 m is moving along the groove with the help of two ideal rollers (massless), connected at the corners A and B of the square, as shown in the figure. At a certain moment of time, during motion the corner A is moving with velocity 16 m/s downward. Find the speed of corner D. (A) 32 m/s (B) 16 m/s
(C) 8 m/s (D) none
9. A uniform cylinder rolls from rest down the side of a trough given by y = x2. The cylinder does not slip from A to B but the surface of the through is frictionless from B to C as shown. If the cylinder ascends up to C, then (Neglect the radius of cylinder).
Q.15. A rod of mass m and length 2R can rotate about an axis passing through O in vertical plane. A disc of mass m and radius R is hinged to the other end P of the rod and can freely rotate about P. When disc is at lowest point both rod and disc has angular velocity . If rod rotates by maximum angle with downward vertical, then find in terms of R and g. (all hinges are smooth)
Q.14. Three identical cylinders of radius R are in contact. Each cylinder is rotating with angular velocity . A thin belt is moving without sliding on the cylinders. Calculate the magnitude of velocity of point P with respect to Q. P and Q are two points of belt which are in contact with the cylinder.
Q.13. A rod of length l is standing vertically frictionless surface. It is disturbed slightly from this position. Let be the angular speed and angular acceleration of the rod, when the rod turns through an angle with the vertical, then find the value of acceleration of centre of mass of the rod.
Q3. A uniform rod of length and mass 2m rests on a smooth horizontal table. A point of mass m moving horizontally at right angle to the rod with velocity v collides with one end of the rod and sticks to it, then:
(A) angular velocity of the system after collision is v/
(B) angular velocity of the system after collision is v/ 2
(C) the loss in kinetic energy of the system as a whole as a result of the collision is mv2 /6
(D) the loss in Kinetic energy of the system as a whole as a result of the collision is 7mv2 / 24
2. A T-shaped object with dimensions shown in the figure, is lying on a smooth floor. A force is applied at the point P parallel to AB, such that the object has only the translational motion without rotation. Find the location of P with respect to C.
Q3. A bead of mass m sides on a hemispherical surface with a velocity v at an angular position . If the coefficient of friction between the bead and hemispherical surface is , Find the magnitude of Angular momentum of bead about O in the position shown.
9. A uniform sphere of radius r starts rolling down without slipping from the top of another fixed sphere of radius R shown in the figure. Find the angular velocity of sphere of radius r at the instant when it leaves contact with the surface of the fixed sphere.