Questions tagged [projectile]
This tag is for questions relating to projectile, object moving through space due to the exertion of a force. The path of a projectile is called its trajectory.
1,397 questions
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If an object falls without friction in a gravitational field, is the average speed independent of the path taken?
If an object falls without friction in a gravitational field, is the average speed independent of the path taken?
Consider a marble falling $1 \; m$ in a vacuum under the influence of the Earth's ...
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Sign convention in air resistance velocity equation
If I try to solve this problem by starting with $ma = mkv - mg$ (since air resistance acts upwards and gravity acts downwards), a number of problems arise. When integrating and applying the initial ...
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Why is a fast moving projectile blown more by crosswind than a slow one?
I am trying to understand this surprising fact (described in Wind Doesn't Blow Bullets) that a fast moving bullet is blown by a crosswind more than if it was just dropped and allowed to fall through ...
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How to calculate the launch velocity to achieve a specific travel time? [closed]
I know how to calulate the time of flight of a projectile given initial velocity and target x and y coordinates (in the plane of the trajectory), but I am completely lost on how to rearrange that ...
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Can compression waves in solids travel supersonically?
Consider a meteor made of, say, pure solid iron entering a certain planet's atmosphere at supersonic speed. Suppose that atmospheric drag severely decelerates the meteor's front, thereby creating a ...
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Why would calculated initial velocity increase with a decrease in vertical displacement for projectile motion?
I was doing a school experiment on how vertical displacement affects horizontal displacement within projectile motion and calculated the initial velocity for the averages. The initial velocity should ...
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How does drag scale with speed for a sphere?
At low speeds, drag scales as the square of the speed. This breaks down in the transonic regime, and for most vehicles drag starts increasing even more rapidly, and then actually decreases afterwards ...
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Does hypervelocity airflow prevent oxidation?
Suppose a 1m radius tungsten sphere is traveling through the atmosphere at sea level at 30 km/s. For a given pressure and surface temperature of the sphere, how rapidly would it oxidize?
Or more ...
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Discrepancy in finding the maximum vertical height of a projectile when the range is given [closed]
This question is of relevance as it debates what the maximum height of a projectile should be when the range is given.
The question in my textbook is:
A cricketer can throw a ball to a maximum ...
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How to derive equation for spring constant in ballistic pendulum? [closed]
Given a ballistic pendulum like the one below that launches a ball at a pendulum using spring force, I need to derive an equation for the spring constant $k$. I find it intuitive to derive the ...
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Parabolic projectile motion in the Paradigm of General Relativity
Apologies if this may sound like a basic question or if somehow if has been asked in another form in this forum, but I could not find a similar question in SE.
In the formalism of general relativity, ...
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Why cannot we conserve linear momentum in this problem?
It is a bullet hitting a rod pivoted at its end (the rod is in vertical plane). At the moment it hits the rod there will be a pivot force on the rod exerted by the pivot. The impulse provided by the ...
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I fire a mortar vertically upwards, with rifling. When it falls, which direction does it rotate? (Or alternatively: how will it behave?)
I fire a mortar vertically upwards, with rifling. When it falls which direction does it rotate?
Let's ignore whether mortars can actually have rifling and assume it does. So, during the upward ...
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What is the Flight Path Angle Derivative?
I have an assignment which involves a rocket flight path. The angle the rocket makes to the Earth is called the flight path angle and when the rocket is in a freefall parabolic curve, there is a time ...
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Apple falling from boat mast
To better understand how gravity and movement works, a common question is to ask where an apple would land if dropped from the top of a mast on a moving boat (let's assume a boat with a motor but with ...