3
votes
1answer
107 views

Forces acting on two balls in a jar [on hold]

Consider the following situation: Two balls are inside a jar with diameter $D$. The balls are uniform in mass and both have the same diameter $d$. Express the forces that acts at the colored dots ...
0
votes
0answers
25 views

A triangle in static position [on hold]

Consider the following: Find the normal force the wall is exerting on the trianlge, given that the triangle is unifrom in its mass with weight $W$, its lengths are $a$ and $b$ as indicated and there ...
1
vote
1answer
38 views

Pushing a crate on a friction floor [closed]

A man is pushing a crate at a constant velocity. there is a friction between the floor and the crate of $$\mu =0.41.$$ The pushing force is directed downward at an angle $\theta $ below the ...
1
vote
2answers
32 views

Finding coefficient of friction between block and plane [closed]

An inclined plane makes angle $\theta$ with horizontal. Upper half plane is perfectly smooth where as lower half is rough. The block of mass m starts sliding from top. If the block again comes to rest ...
0
votes
1answer
50 views

What happens when the speed of a body is less than optimum speed?

Yesterday I learned about optimum speed. My teacher told that optimum speed is the speed with which one can take turns on banked road without wear and tear. $v_0=\sqrt{rg\tan\theta} $, $v_0$= ...
3
votes
1answer
98 views

Determine the acceleration in a double Atwood machine

Trying to solve the following double Atwood machine: Suppose there is a mass of 12kg hanging on an ideal rope that wraps around an ideal pulley, and that the other end of the rope is attached to ...
0
votes
1answer
33 views

Kinematics - moving body [duplicate]

If I have an inclined plane, which has acceleration $\alpha$, will a block placed on the inclined plane slip back with the same acceleration? (considering that the surface is frictionless)
1
vote
1answer
41 views

Tension in an Atwoods machine conceptual?

Assuming $T_1$ is the force that acts on box $1$ and $T_2$ is the force that acts on box $2$. Exactly what causes the Tension? Why does $T_1 = T_2$? The problem is we are told to memorize that ...
0
votes
3answers
55 views

Solving for Normal Force

I'm working through The Nature of Code, which is an awesome book, lots of fun. I've come across Exercise 3.13 and I'm not sure how to solve it. I'm assuming that the force of gravity and the force of ...
1
vote
2answers
72 views

Which Force would help find the mass?

A and B are connected to a rope. A constant upward force 86.0N is applied to box A. Starting from rest, box B descends 12.1m in 4.70s . The tension in the rope connecting the two boxes is 32.0N. What ...
0
votes
0answers
45 views

Can't work out how the following free body diagram was created

I've been asked to draw a free body diagram of the following stepped bar setup: $ P = 10kN \;and\; Q = 30kN$ The one shown in the answer is the following: Could someone explain to me how this ...
0
votes
1answer
167 views

Find the tension and angle from a vertical of a rope hooked up to an object

Below is the homework problem I am working on: A 18.3-kg object hangs in equilibrium at the end of a rope (taken as massless) while a wind pushes the object with a 63.9-N horizontal force. Find ...
2
votes
1answer
187 views

How is circular motion possible on a banked road when there is no Friction?

It is given here that the maximum safe speed of a vehicle on a banked road having coefficient of friction $0$, is $V =\sqrt{R g \tan \theta}$, where $\theta$ is the angle of banking. I can't ...
0
votes
2answers
128 views

Is my free diagram of a spring stretched on one end and attached to the wall on the other end correct? [closed]

Consider the following figures. The top one shows the construction of a spring where its left end is attached to the wall and its right end is stretched by a force. The bottom one is supposed to be ...
0
votes
1answer
102 views

Confusing Classical Mechanics Question

I don't want this to be a "do my home work question" so please tell me how I can make this question helpful for other people. In my physics assignment I found the question below. I'd think that both ...
3
votes
1answer
151 views

Force on bolt holding up jet engine on plane

I am to solve the following: A jet engine of mass $m$ is fastened to the fuselage of a passenger jet by a bolt. During flight, the plane encounters turbulence, which suddenly imparts an upward ...
-6
votes
3answers
214 views

Can you lift a basket up while standing inside it? [closed]

Suppose you stand in a basket and you try to pull the handles of the basket. Will you be able to lift the basket from ground? Similarly, Baron M√ľnchhausen allegedly pulled himself and the horse on ...
2
votes
1answer
846 views

Static Friction in Free Body Diagram (FBD) of Car parked on Incline

I'm working on a sample problem and it asks on how steep of an incline can a car park? From what I learned the friction is in the opposite direction if there was motion in said friction-less ...
-1
votes
1answer
575 views

How should I draw this free-body diagram?

The horizontal force P acts on the rim of the homogeneous cylinder of radius R and weight W. Determine the smallest coefficient of static friction that enables the cylinder to start rolling up the ...
1
vote
1answer
2k views

Two problems with free body diagrams. Contradictions (solutions are provided)

This problem is similar, but also different question from my previous question. They are both unfortunately long. Problem/Solution #1 ! ! Quick Concept Check a) Could someone briefly explain to me ...
1
vote
2answers
2k views

How do I properly use Newton's Third Law and Free Body Diagrams?

A force of 14.0N is applied to a block as shown in the diagram below ! If the coefficient of friction is between the surface and the blocks is 0.35 a) What is the acceleration of the two blocks? ...