This problem is similar to what I have done before here. I think since the system is in equilibrium, that is both bodies are at rest, net force on each should be zero. So to balance the forces in all directions we need only friction forces on each in upward direction. So the force on B due to A...
1. ##-f_k\cos\theta-T\cos\theta+F_n\cos\alpha=m_2a_x##
2. ##f_k\sin\theta+T\sin\theta+F_n\sin\alpha-m_2g=-m_2a_y##
3. ##T-m_1g=m_1a_y##
I am unable to get anywhere. There are accelerations in x , y directions.
I need the value of acceleration. Then I can simply use ##s=ut+\frac12at^2##
Hello, everyone.
This problem is easy if you assume that the friction between the blocks and the platform is the maximum possible. Then the normal force is 0. But how can you show that the normal is 0 even when the friction is less than maximum?
Thank you for your help.
Hello, thanks for the attention. Well, knowing that the only acting force is the gravitational force, I stated that ##U=-MgH## for the ##M## mass block and that ##U=mgh## for the ##m## mass block. After that I divide the two and got the relationship for the alternative "a". For alternative "b" I...
the acceleration of the center of mass is ##a_{cm} = F/(M+m)##
I considered the forces on the block of mass m(when the system is at maximum extension) I got the equation $$kx - \frac {mF}{(M+m)} = ma_{cm}$$
and from that I got the value of the maximum extension $$x = \frac {2mF} {k(M+m)}$$ which...
if the applied force F >(M+m)g/##\mu## the force of friction between the two blocks should become f=N##\mu## and since the normal reaction will be greater than what it should be to keep the block m at rest with respect to M, will the mass m accelerate upwards.
in short,for let's say a very...
So, for this question first I did a free body diagram in the perpendicular x-y axes, and, I got some equations with the normals, but the answer is independent of normal forces. So, I'm not sure how to eliminate the two normals. Further I find it quite weird that big block-A doesn't come into the...
I've problems understanding why the kinetic energy of the string is only
$$T_{string}=\frac{1}{2}m\dot{y} $$
Why the contribution of the string in the horizontal line isn't considered?
Hi,
I am quite confused about how to approach this problem. I have seen variations of this problem where there is a heat engine between two blocks, but in this case the surroundings are massless, so I don't believe that approach will work here.
Method:
I have first started with the case that...
Summary: In the situation given, all the surfaces are friction less, pulley is ideal and string is light, F=mg/2, Find the acceleration of block 2 ?
Here's the diagram--
My attempt- (i) I tried to solve the question by making FBD of the two blocks, but i am not able to draw all the forces...
Equation 1: T = Ma1
Equation 2: mg - 2T = ma2
Equation 3: a1 = 2a2
Since a1 = 2a for equation one I get T = 2Ma1
mg - 4Ma1 = ma1
mg = 4Ma1 + ma1
mg = 4a1(M+m)
a1= mg / 4M+m
Not sure if this is correct. Can someone please help to make sure I'm doing this right?
Thanx
Homework Statement
Two blocks of iron, one of mass m at 10.0C and the other of mass 2m at 25.0c, are placed in contact with each other. If no heat is exchanged with the surroundings, which of the following is the final temperature of the two blocks?
A)10
B)15 .
D) 20C ( this is the answer)
The...
Homework Statement
[/B]
##m=3kg##
##M=2kg##
Coefficient of static friction between m and M ##\mu_1 = 0.6##
Coefficient of static friction between M and the ground ##\mu_2 = 0.8##.
The rope is weightless, does not stretch, and the wheel is frictionless.
What is the maximum force ##F## that...
Homework Statement
The coefficient of kinetic friction between the block of mass m1 = 2.5 kg and the plane in Fig. 6 below is 1/6. Find (a) the acceleration of the block and (b) the tension in the string. Take g = 10 m/s2.
Homework Equations
Fnet=ma
The Attempt at a Solution
please i don't...
Homework Statement
a mass m1 is attached to a second mass m2 by an acme (massless, unstretchable) string. m1 sits on a table with which it has coefficients of static and dynamic friction μs and μk respectively. m2 is hanging over the ends of a table, suspended by the taut string from an acme...
Homework Statement
Two blocks m1 and m2 are connected by a weightless rod are on a inclined plane of ∅=37° and μ =0.25 .What is the common acceleration and Tension of rod if m1 is 4 kg and m2 is 2 kg such that the 4kg block is the upper block.
OPTIONS
A =4m/2 T=0
B =2m/2 T=5N
C =10m/2 T=10N
D...
Let's say that we have two blocks - 2 kg and 1 kg.
They are connected with a rope that can stand the maximal tension of 20 N.
Does the maximal force we can apply to the block so that the rope does not break apart depend on the choice of the block?
Homework Statement
Two blocks have a spring compressed between them, Block A (mass 1kg) and block B (mass 3kg) . The spring has force constant 720 N>m and is
initially compressed 0.225 m from its original length. For each
block, what is (a) the acceleration just after the blocks are released...
Homework Statement
Two block M1 and M2 rest upon each other on an inclined plane. Coefficient of friction between surfaces are shown. If the angle θ is slowly increased, and M1<M2 then
Options :
1- Block A slips first.
2- Block B slips first.
3- Both slip simultaneously.
4- Both remain at...
1. Homework Statement
Problem in pictures
Homework Equations
f=ma
The Attempt at a Solution
So the tension force is 20N, i took the frictional force on the bottom of the block as 3*9.8*.4 because the bottom of the block has a total mass of top block and bottom block = 3kg, so i have 20N -...
Homework Statement
Two blocks each having masses of 3.3 kg are connected by a wire CD and the system is suspended from the ceiling by another wire AB.The linear mass density of the wire AB is 10X10^-3kgm^-1 and that of CD is 8X10^-3.The speeds of the transverse waves produced in AB and CD are...
Hello,
I have an issue regarding a constraint related to an angle:
Suppose I have masses 'A' and 'B' on an inclined plane ( of mass 'C') attached by a pulley.
I place my origin as shown and I want to find a constraint relating angle β.
so, I saw my classmate writing as follows to find...
Homework Statement
Everything that can be used is in the picture.
μ is the coefficient of friction between both B and A and A and the surface.
A is moving upwards the surface with a certain acceleration.
B doesn't move in relative to the surface.
1. Why the direction of A's motion must be...
Homework Statement
Now these two blocks are pulled separately by x1 and x2 distance. Find the frequency of shm
Homework Equations
a = -w^2 x
The Attempt at a Solution
Now after m1 being pulled, it moves with acceleration
a1=Force of spring/m1.
acceleration of block 2 =
a2=/force of...
Homework Statement
Two blocks slide on an incline of angle \theta . Block 1 has mass m1 and coefficient of kinetic friction μ1 with the surface, block 2 has mass m2 and coefficient of kinetic friction μ2. The gravitational acceleration is g.
In terms of these parameters, under what condition...
Two small blocks, each of mass m, are connected by a string of constant length 4h and negligible mass. Block A is placed on a very rough tabletop as shown below, and block B hangs over the edge of the table. The tabletop is a distance 2h above the floor. Block A is then released from rest at a...
I am currently working on this problem and I am stuck as to how to approach or solve it. The problem is that a block of mass 11000kg is sliding down a slope with a height of 1000m, angle of 40 degrees and the coefficient of friction between the block and the slope is 0.1. The block splits...
Homework Statement
Two blocks of masses m, and m2 are connected by a
spring of spring constant k.
Suppose each of the blocks is pulled by a constant force F
Find the maximum elongation spring will suffer and the distances moved by the two
Homework EquationsThe Attempt at a Solution
the two...
Homework Statement
The 1.0 kg block in the figure is tied to the wall with a rope. It sits on top of the 2.0 kg block. The lower block is pulled to the right with a tension force of 20 N. The coefficient of kinetic friction at both the lower and upper surfaces of the 2.0 kg block is μk = 0.300...
Homework Statement
[/B]Block 1 of mass 3.0 kg is sliding across a flooe with speed ##v_1=2.00 \frac m s## when it makes a head-on,one dimensional,elastic collision with initially stationary block 2 of mass 2.0 kg.The coefficient of kinetic friction between the blocks and the floor is...
Homework Statement
In the setup , block C remains at rest and block A move towards left when system is released . If velocity of A is 'u' towards left at an instant , what is the vertical component of velocity with which B descends .What is the horizontal component of velocity of B at this...
Homework Statement
System comprised blocks, a light frictionless pulley and connecting ropes (see diagram). The 9.0kg block is on a perfectly smooth horizontal table. The surfaces of the 12kg block are rough, with μk = .2 between the two blocks. If the 5.0 kg block accelerates downward when it...
Homework Statement
a)Find the magnitude of the acceleration of the two blocks in (Figure 1) . Assume the top block slides without friction on the horizontal surface.
b)If the 12-N block in (Figure 1) is replaced with a 12-N force pulling downward, as in (Figure 2) , is the acceleration of the...
Homework Statement
A block of mass m1= 20.0kg connected to a block of mass m2 =30.0 kg by a massless string that passes over a light, frictionless pulley. The 30.0-kg block is connected to a spring that has negligible mass and a force constant of k =250 N/m as shown in Figure P8.64. The spring...
Homework Statement
A cube with 1 kg mass is put on top of a bigger cube with 3kg mass and 1 meter edges.
If 10 N force is exerted on the bigger cube, while the maximum friction between the cube surface is 2 N, and g=10m/s^2 , then at one time the small cube will fall to the floor.
The time...
Homework Statement
Two crates are stacked on top of each other on a horizontal floor. The coefficient of static friction between Box A and Box B is 0.6. The coefficient of static friction between Box A and the floor is 0.2. A force of 100 N is applied parallel to the floor on Box B. The boxes...
Homework Statement
Block 1 (mass 2 kg) is moving rightward at 10 m/s and block 2 (mass 5kg kg) is moving rightward at 3 m/s. The surface is frictionless, and a spring with spring constant of 1120 N/m is fixed on the left side on block 2. When the blocks collide, the compression of the spring is...
1. Homework Statement
The problem is shown in the photo above. I would like to discuss part B.
Homework Equations
conservation of linear momentum
The Attempt at a Solutionthe solutions say that we should have the following approach:
Mb*vb = [Mb + Ms] * vFinal.
Plug in the numbers and get vF...
Homework Statement
Two blocks, A and B , are being pushed on a frictionless surface by a froce of 30 N to the right, .Block A has a mass of 2.0kg, Block B, being pushed by Block A is 4.0kg. Calculate the magnitude of the force that block B exerts on Block A.
Homework Equations
f=ma
The...
Homework Statement
Two blocks are of the same mass M. One lies on a frictionless ramp with slope θ, while the other one, connected by a rope, hangs by a pulley with a moment of inertia of I and a radius of r. Find the acceleration of the two blocks.
I don't have an actual picture, but this one...
Homework Statement
A block of mass m1 = 3.70 kg on a frictionless inclined plane of angle 30.0° is connected by a cord over a massless, frictionless pulley to a second block of mass m2= 2.30 kg hanging vertically. What are (a) the magnitude of the acceleration of each block and (b) the...
Homework Statement
Block A and block B are on a frictionless table as shown in Figure 2. Spring 1 connects block A to a frictionless peg at 0 and spring 2 connects block A and block B. Their masses are respectively mA=0:45 kg and mB=0:32 kg. When the blocks are in uniform circular motion about...
Two 2.4-kg blocks are connected by a string draped over the edge of a slippery table, so that one block is on the table and the other is just hanging off the edge. A restraint holds the block on the table in place, and the string is 0.50 m long. After the restraint is removed, what speed does...
Homework Statement
Blocks A and B each weight 170 lb and rest on frictionless surfaces. They are connected to one another by cable AB. Determine the force P required to hold the blocks in the equilibrium position shown and the reactions between the blocks and surfaces.
Hint given: This...
Homework Statement
Two blocks of weight 50N and 200N are connected by a cord rest on two inclined planes .determine the maximum tension in the cord when limiting friction condition develop in both blocks
R1=Reaction of weight 50N
R2=reaction of weight 200 N[/B]Homework Equations
for block of...
Homework Statement
A mass m1 = 5.1 kg rests on a frictionless table and connected by a massless string over a massless pulley to another mass m2 = 5 kg which hangs freely from the string. When released, the hanging mass falls a distance d = 0.83 m.
Homework EquationsThe Attempt at a Solution...