# Tagged Questions

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### Calculating the velocity given the radius , period, centripetal force, and mass [closed]

In university physics homework their is a practice question requiring the calculation of the velocity given the radius , period, centripetal force. I am completely baffled as to whqt formula to use ...
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### Why isn't jumping against a wall an elastic collision?

According to this calculator http://www.abecedarical.com/javascript/script_collision1d.html when low mass object hits high mass object it is reflected gaining opposite velocity almost the same as ...
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### Spinning theoretical object moving faster than the speed of light [duplicate]

Let's say you have the Earth, or any celestial body, spinning as it is. What if you build a tower from the surface, and extended it out into space. If it was built far enough, could the furthest end ...
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### How can I calculate the initial velocities of a set of objects with a consistent force?

I'm trying to figure out which object would have the largest time of flight when launched from a slingshot. To do this, I need the initial velocity. How can I calculate this if I know the mass and ...
3k views

### Terminal velocity of two equally shaped/sized objects with different weights?

I've tried doing research on this and there are some similar questions. However, they have slightly different scenarios and to make sure I understand things perfectly, I wanted to word it into my ...
3k views

### What is the difference between impulse and momentum?

What is the difference between impulse and momentum? The question says it all...I know the second of of them is mass * velocity, but what is the first one for, and when is it used? Also, what are its ...
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### Conservation of momentum equation, how do I factor out v0Final and v1Final?

I am trying to figure out an equation for conservation of momentum. So, If combined momentum before and after the collision is the same, and momentum is velocity times mass, then for 2 objects (A,B), ...
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### At what point does a projectile leave a slingshot?

Assuming a frictionless / "perfect" environment, and given a ball held in an elastic sling (like a hand-held catapult) where the pocket is lighter than the projectile itself, what is the point at ...
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### Motion is relative, right? And most pop sci relativity explanations are somewhat incorrect?

On page 20 of A Brief History of Time: . . . all observers should measure the same speed of light, no matter how fast they are moving. But in an observer's frame of reference, they're actually ...
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### Is it possible to calculate weight of person with sensors found in today's smartphone?

Is it possible to calculate the weight of a person by only using his smartphone, some action he must perform (jump, rotate etc.) and some data like his height or age. Current smartphones have the ...