What is Falling body: Definition and 36 Discussions
A set of equations describe the resultant trajectories when objects move owing to a constant gravitational force under normal Earth-bound conditions. For example, Newton's law of universal gravitation simplifies to F = mg, where m is the mass of the body. This assumption is reasonable for objects falling to earth over the relatively short vertical distances of our everyday experience, but is untrue over larger distances, such as spacecraft trajectories.
I'm curious about impact on falling object, so i have taken initiative to solve this problem.
I considered only force on the falling object would be its weight and taken F=mg. With only limited data m=.25kg and drop height h=1m.
Pondering on this consideration practically, it will have more...
If (a) is correct, the answer would be 34.3m.
If (b) is correct, the answer would be 9.8m.
I want to know exactly which one is meant by the question and the reason behind that. Personally i think its a.
Homework Statement
This question is actually two question. We have two hollow frames - one is rectangular and another is triangular. the rectangle is rotated and fixated such that the angles in shape are ##\alpha , \beta = 90 - \alpha## and the angle of triangle is ##\alpha##. We have two balls...
A freely falling body (falling in earth) accelerates with time. However, an object inside the body remains at rest (if it was initially at rest) or moves with a constant velocity if it was initially moving with constant velocity. In other words a frame fixed to the body is an inertial frame...
Homework Statement
In this problem you will do numerical computer calculations. A skydiver of mass 75.0 kg jumps out of a plane at an altitude of 30.0 km above the surface of the Earth. His parachute fails to open. Assume there is no horizontal motion and the initial velocity is zero. We...
Homework Statement
Solve the differential equation, dt/dv= 1/g (1/1-a^2*v^2) where a = (k/mg)^1/2 to yield v= 1/a(1-e^-2agt/1+e^-2agt).
Homework Equations
F=ma
Newton's 2nd Law
Integration Laws
The Attempt at a Solution
See image. I think I'm getting messed up on the integration laws.
Homework Statement
The speed of a falling body might be based on the observation that the velocity of a falling object seems to increase the further it has fallen. Model the hypothesis "The speed of a falling object is proportional to the distance it has fallen" as a differential equation...
Homework Statement
A plate is fixed to the ceiling by two wires and to the wall by a single wire.
The wall wire is cut. Calculate the tension in the two remaining wires.
mass = 800 kg
g = 10m/s²
Dimensions in sketch
Homework EquationsThe Attempt at a Solution
Equations:
Ra*cos30 + Rb*cos30 =...
Homework Statement
Most physics problems that involve a falling body assume constant acceleration. How does one account for the changing acceleration if a body is dropped from a very high altitude?
Homework Equations
With constant acceleration, d = (1/2)at^2 or t = sqrt(2d/a)
but a is not...
I am a writer, and this is the opening scene in a story I'm currently working on. A girl weighing 110 lbs gets sucked across a room, about 50 yards, then hits the wall. Her boyfriend knows that if he doesn't get her into a stasis pod within 10 minutes, she'll be dead from the massive internal...
Here is an unsettling question from a practice set that I've been working on today. Unsettling because the answer key contradicts my answer so I need a second thought.
A pingpong ball and a golf ball are dropped in a vacuum chamber from the same height and at the same time. When they have...
Homework Statement
Prove that the enrgy of a falling body remains constat using the derivate of a function
Homework Equations
We need to prove that:
\frac{mv^2}{2} + mgh is constant, trhat is its derivate equals 0
The Attempt at a Solution
Let the positive direction be...
Hello, my question id the following: when using Tsiolkovsky's equations to determine the velocity of a body after certain period of time, when the engine of a (space)craft is running, life is simple.
But how do you calculate the falling rate of an object that is constantly falling, and then...
Hello,
I don't think I really understand the derivation of an equation of motion for a falling body under the force of Earth's gravity... I'm a little ashamed by this. I haven't been able to find someone asking quite the same question as I am about to ask.
I completely understand that the...
Okay guys, a different one for you. I am in the planning stages of building a structure that will simulate a motor vehicle collision. The process would be a motor vehicle will be hoisted to a specific height and then dropped. The height, and the weight of the vehicle will determine the...
Hi everyone,
I have read a few different ways of looking at this problem, and it's one of those things where I am happywith the answer, just not how to get there using proper mathematics. My lecturer described this with some complex integrals involving E (but I'm not sure what that is!) but I...
Let's say that body with rest mass m0 is falling toward gravitating body from infinity.
Near gravitating body it falls with speed v=\sqrt{\frac{2MG}{r}}
Is it right that relativistic mass of body falling at speed v near gravitating body is equal to the rest mass of the same body at infinite...
Homework Statement
A 7500-kg rocket blasts off vertically from the launch pad with a constant upward acceleration of 2.25 m/s^2 and feels no appreciable air resistance. When it has reached a height of 525 m, its engines suddenly fail so that the only force acting on it is now gravity.
(a)...
Homework Statement
Under some circumstances a falling body B of mass m encounters air resistance proportional to its instantaneous velocity v. Use Newton's second law to find the differential equation for the velocity of v of the body at time t. Recall that acceleration a = dv/dt. Assume in...
What is the difference between these two equations.
m dv/dt = mg - kv
and
m dv/dt = mg - kv^2
as the equation modeling a falling body with air resistance?
Homework Statement
With what power we should force the body with mass 5 kg to make it fall down vertically with acceleration 15 m/s²?
a = 15 m/s²
g = 10 m/s²
m = 5 kg;
F - ?
Homework Equations
F = m×a;
F = m×g;
The Attempt at a Solution
F = m × (g + a);
But this is not right...
When a body falls from a height (h) under gravity,the work involved is mgh. How do you describe this work? Is it 'work done by the force (gravity) on the body' or 'work done by the body'. The confusion is, if work is done on the body the body gains energy; but if work is done by the body the...
A rocket shoots upward with a velocity of 500 feet/sec. Neglecting air resistance, how high will it travel? Is that even enough info to solve the problem? I don't remember how to solve that.
Homework Statement
Hi all - apologies now if there is a thread on this very problem, but I have searched the web and still can't seem to find something to help me.
Okay the problem: I am trying to solve a problem that has been bugging me and I think I am missing something
I have ball...
Hi this is my first post thanks to who ever contributes!
Homework Statement
A man drops a ball from the top of a 22m building. At the same instant his friend below throws a ball upwards at 22 m/s. What distance from the ground do the two balls meet.
Ball A
-------
v1 = 0 m/s
a = 9.8m/s down...
a small body, with the mass of M is dropped from an infinite height falling freefall, the air's friction on the body is defined by ==>f=-kv^2, k=const.
find the velocity after an infinite amount of time.
using Newtons 2nd law,
F=ma=mg-kv^2
a=g-(kv^2)/m
now, how do i find the velocity...
1. Neglect air resistance. A suspention bridge spand the colorado river at a height of 321 meters. Consider a 75kg bungee jumper, and a 200m bungee cord which obeys hooke's law (once it reaches its unstreched length).
a) calculate the spring constant k, so that the jumper halts just above...
Homework Statement
Consider a body falling from a tower in the northern hemisphere at approx 40 degrees latitude. The body is seen to have a displacement to the east. Explain the origin of this displacement qualitatively from the point of view of a non-inertial observer. What local effect is...
Homework Statement
A lunar lander is making its descent to the moon Base I. THe lander descends slowly under the reto-thrust of its descent engine. The engine is cut off when the lander is 5.0m above the surface and has a downward speed of 1.5m/s. With the engine off, the lander is in free...
1.For a freely falling body under gravity:
1.Why does the slope of S vs. t^2 gives g/2? Why not g itself?
2.Does the graph exhibit linear relationship?
I have studied that the slope of a velocity time graphy gives the acceleration directly. Now when we make a graph for S...
Is there gravity in the process of falling body?
The answer is not.
Galileo demonstrated that the acceleration of falling body is not concerned with mass, volume and chemical elements. This is Galileo phenomenon. Newton and Einstein attempted to use their theory, gravity law or general...
Hi,
We were assigned a problem set for homework, a total of 7 problems. Below are the questions, and the work I used to get the answer. I'm just looking for a second set of eyes to point out any mistakes I may have made.
thanks!
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6.(a) How long will it take a freely falling body...
I need an answer for a practical question. Say an unconscious (but rigid) person fell out of a helicopter that was not moving. If you DON'T ignore air resistance and terminal velocity, what would be his displacement after a given time (assuming the initial position is at zero, for...
A "Simple" Relativity Question...
I was asked this question on another forum, and it seems easy at first glance but may be more subtle: What would an observer on a very massive star (yeah, a well insulated observer) see about a small body falling in toward the star, from very far away?
Would...