# Questions tagged [forces]

This tag is for the classical concept of forces, i.e. the quantities causing an acceleration of a body. It expands to the strong/electroweak force only insofar as they act comparable to ‘classical’ forces. Use the [particle-physics] tag for decay channels due to forces and [newtonian-mechanics] or one of the other subtopics of [classical-mechanics] for the dynamics of classical systems.

9,051 questions
Filter by
Sorted by
Tagged with
1 vote
37 views

### Vertical Circular Motion ($u$ minimum)

In vertical circular motion, when we consider motion of a pendulum bob, while finding minimum velocity to complete VCM, we take Tension=0 at highest point and velocity at highest point is not equal to ...
• 13
45 views

1 vote
26 views

### Determining Tension in a Massless String Under Various Configurations: Straight, Over a Pulley, and Around a Fixed Nail

If a massless string is stretched by applying extensive forces of magnitude 𝑥 on both sides, a tension 𝑇 is developed at every point of the string. If the same massless string is placed over a ...
3k views

### How does a vehicle's brake affect the friction between the vehicle and ground?

When brakes are activated in a vehicle it decelerates. Analysing its motion, there can be only one force that can be responsible for it: the friction between the car and the ground. So does braking ...
18 views

### How significant is the parabolic arch effected with an incline versus a decline in angle versus a decline in angle . For example throwing a dart

A dart players height can vary as can the height in which they raise their arm to aim. Is there less parabolic arch when throwing at the same strength from above the target compared to below, due to ...
1k views

### Problem with internal forces in spring following Hooke´s law

When looking at Hooke's law for the entire spring the force is $kx$. But what happens when analyzing segments of the spring in order to look at the internal forces? Imagine a spring of length $x$ that ...
• 183
71 views

### Why do objects with greater length feel heavier - and how to calculate perceived weight?

Consider this situation: As part of some training, you are asked to pull an object that is 100 feet long, weighing approximately 218 pounds across a distance of 310 feet (fire hose across concrete if ...
949 views

### Is the work I do on the object always equal in magnitude but opposite in sign to the work the object does on me?

According to the definition of work, the work I do on an object is equal to the force I apply to the object multiplied by the distance the object moves. By Newton's third law, the reaction force (F21) ...
• 305
70 views

### How is the expression for work in this problem derived?

In this solution to the problem I found, the work expression comes out to be the force times $d$, the difference in distances from the collar to the force origin at positions A an B. I can't for the ...
26 views

### Can two objects of different mass experience the same air resistance? [duplicate]

This question is assuming that the objects have the same shape and size, but different masses. I know that all objects have the same gravitational acceleration on earth, which is about 9.8 m/s^2. ...
• 539
35 views

### Two weighing scales compressed inside a solid frame

Two weighing scales are placed on top of each other at the bottom of a solid enclosed frame. At the top of the frame a linear actuator is attached. The linear actuator can extend and press down upon ...
47 views

### What happens when both magnetic field and electric field is applied to a charged particle?

Now what exactly happens when magnetic field and electric field is applied perpendicularly? What happens when they are not perpendicular? In the question, it says that a magnetic field and electric ...
• 83
60 views

### In a magnetic field, does the force act on the midpoint of the current carrying wire?

Here, it says that the force acts on the middle points of the wires, but why? What do they mean by when they are saying that the forces 1 and 3 are acting on the same line of action? How does that ...
• 83
22 views

### Is it necessary for constant mass of system to use Newton's 2nd law? [duplicate]

Is it necessary for the mass of the system to be constant to use Newton's 2nd law (here the mass of the bodies in the system can change but the total mass of system can't)
• 51
92 views

### What's the need for 2 separate laws of motion when the first law is an special case of the second one? [duplicate]

The first law of newton tells us that a body shall remain unaccelerated when the net force acting on it is 0, but the second equation gives us the relation F=ma so, ain't the first law just an special ...
• 51
1 vote
53 views

• 51
57 views

### When is it appropriate to say Newtonian gravity is a force? When is it not appropiate? [closed]

Please help me understand the notion of force when it is applied to Newtonian gravity. From my understanding forces in physics involve interactions with at least 2 objects and can cause an ...
• 431
88 views

### How would I calculate the force of friction between an RC car and a carpet?

I'm working on a physics project where I aim to demonstrate how different surfaces impact the velocity and acceleration of an RC car due to friction. How can I calculate the coefficient of friction ...
58 views

### Forces acting on a bouncing ball

I have encountered the following question while completing a multiple-choice exercise on dynamics, more specifically Newton's third law: A ball falls vertically and bounces on the ground. The ...
1 vote
49 views

### Finding Exterior Confining Pressure from Interior Pressure Point for a Solid Disk

Essentially, I've been wrapping the pictured object tightly with string to exert a confinement pressure on its exterior. It's been difficult however to make a good estimate of how much pressure is ...
52 views

### Does Newton's third law give bouncing objects more energy?

I understand that this question seems nonsensical, so I will do my best to explain. When a ball, or any object, bounces, energy is conserved and converted to other forms like heat, sound, etc. However,...
• 539