All Questions
Tagged with everyday-life free-body-diagram
31
questions
7
votes
6
answers
3k
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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 ...
- 95
17
votes
8
answers
7k
views
Why is it possible to keep an object, say a book, horizontal while holding its corner?
When holding a book from its corner with two fingers in a pinched position, the fingers act as a sort of hinge, and the book is free to rotate about this corner only. The external forces acting on the ...
- 349
1
vote
0
answers
54
views
A Hotwheels Problem [duplicate]
I have a Hotwheels track set. It has a looped structure such that at some point in the car's trajectory, it becomes upside down. But in such a situation, it doesn't fall to the ground. I understand ...
- 1,064
4
votes
4
answers
1k
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Too fast into a corner: should I brake?
Thought about this during a recent road trip. Suppose I'm driving in a corner and realize I went in too fast, and I'm worried that the tires are about to slide. Should I slow down?
Assume the corner ...
- 265
37
votes
7
answers
6k
views
Can spinning arms really help you balance on the edge of a cliff?
This is how many cartoons depict a character about to fall from the edge of a cliff. You can see movie characters do it. You can also see real people doing it. But does spinning arms like that ...
- 12.5k
0
votes
2
answers
281
views
Direction of friction while walking on ground
Consider a man walking on a rough ground towards the east. If this was the case, the friction should have acted towards the opposite direction, i.e., west. Instead in real life, in the same case, the ...
0
votes
3
answers
2k
views
How does a car actually move?
Physics textbooks say that the car's engine spins the wheels which put a force on the ground, which pushes the car (somehow) by Newtons 3rd law. But how does the ground actually make the car move? If ...
- 3
1
vote
1
answer
101
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How can I accelerate the linear speed of a spinning rock on a string when the rope can exert no net torque on the rock?
If I take a rock attached to a mass-less rope and start spinning it over my head (or on a friction-less surface, I don't think it matters) I can accelerate the linear speed of the rock (I can spin it ...
- 535
-1
votes
1
answer
70
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For a rear wheel driven motorcycle, why is the reaction force acted on the rear wheel greater than that on the front wheel?
Is it because there’s a greater frictional force on the rear wheel as it is responsible for the acceleration of the motorcycle?
- 19
34
votes
8
answers
7k
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Why does twisting a cork make it easier to remove from a bottle?
When we want to remove a cork from a bottle first we turn the cork. Turning in one direction makes it easier to remove in the axial direction.
Does anyone know something more about this?
1
vote
5
answers
470
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Please explain the walking mechanism
When a person walks, he exerts a force on the road, lets say $F$, and the road exerts a force on the legs (friction), lets say $f$. Newton's third law says that $F = f$, so why is $f - F = ma$? Where ...
- 817
1
vote
1
answer
992
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How does friction helps us to move/walk?
We all know that it is friction which helps us to walk on any surface. If there were no friction we could not walk or might walk but very slowly. According to Newton's 3rd law, if we apply an oblique ...
- 598
1
vote
3
answers
219
views
Difference in weight while pulling weights
Let's say you are using a standard pulley gym machine to lift some amount of weight. If while you exercise you are standing on a weighing scale. What variations in weight if any would occur?
Does it ...
- 113
57
votes
8
answers
10k
views
Principle of physics used in the lift of skateboard
What is the principle of physics used in this popular stunt?
Initially, I thought aerodynamics due to an increase in the angle of attack, but its magnitude is not sufficient to balance the whole body ...
- 724
9
votes
3
answers
426
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Physics of the trikke tricycle
I love my trikke, but I still do not understand what propels it forwards.
It is very clear that the energy comes from my legs and not from my arms (I only have to touch the handle bar ever so lightly)...
- 567