0
votes
1answer
36 views

Catapult projectile with different mass [on hold]

We have a physics law. We made catapult and we have to launch a water balloon. However before that we have to know where the water balloon will fall. We don't have radars or stuff like that to ...
1
vote
1answer
35 views

Problem with formula for parabolic motus

I know that the path made by an object thrown in air with velocity $v_0$ with an angle $\alpha$ is: $$y=x \cdot\tan \alpha - \frac {gx^2}{2v_0^2\cdot \cos^2 \alpha} $$ At school we had to use this ...
-1
votes
0answers
13 views

Motion in a straight Line [on hold]

A stone is projected from a height of 300m and at same time another stone is projected vertically upwards with a velocity of 100m/s Find when and where the two stones meet
0
votes
0answers
17 views

Falling with air resistance speed as a function of distance [closed]

Starting at 0 velocity and falling with air resistance $-mkv$, find the relation between speed and the vertical distance that an object falls. I went through the problem to find the equation of motion ...
0
votes
1answer
35 views

Projectile motion with air resistance limit question [closed]

I have the equation for the max height $h$ of a projectile launched directly upwards with speed $v_0$ and air resistance force $-mkv$. I am trying to calculate the limit as $h$ goes to ...
0
votes
1answer
24 views

Confusion about horizonally projected body

DESCRIBED IN IMAGE CLEARLY In the text book, I got the initial velocity of x-component initial velocity Vxi, Vxi = Vi cos(0); (0 = zero) but what if it is like the picture i showed, first it was ...
1
vote
1answer
44 views

Projectile Motion Tricky Problem [closed]

A particle is projected from point A with a velocity u at an angle theta to the horizontal. At a certain Point B, it moves at right angle to its initial direction. what is the time taken from A to ...
1
vote
1answer
24 views

How to find the maximum height with a loss of 5 J of energy due to air drag [closed]

Can someone please help me to figure out how to use the 5J of energy into my equation for the maximum height. I know that the maximum height is given by, $$h_{max}={(v_f-v_i)^2 \over 2g}$$ but I'm ...
0
votes
3answers
66 views

Finding maximum height of projectile motion using potential/kinetic energy

I'm having some difficulty understanding how to find the maximum height using conservation of force. This is the picture I'm looking at: and this is how you find it: $$\begin{align*} ...
0
votes
2answers
49 views

Calculate average speed of projectile with air resistance

There's a project that I'm working on that been bugging me for awhile. The project involves this senario: A projectile is released at 1000 feet per second and moves in a straight line infinitely ...
1
vote
1answer
49 views

Projectile motion with drag force of the form $\vec f =-k \vec v$ [closed]

An object is fired with initial velocity $v_0$ at inclination angle $\theta$ above the horizontal. Drag force in the air is taken into account and is of the form $\vec f =-k \vec v$. Knowing that the ...
2
votes
0answers
27 views

What will be the time taken by a stone to reach the ground if it is thrown with velocity $v$? [closed]

I was studying from my reference book and I got this question. I tried solving it by finding the total distance n average velocity but it didn't work please help me out.
0
votes
1answer
20 views

Projectile velocity and component $x$ and $y$ velocities

So the equations for the X and Y velocity given $\theta$ and $V_0$ are $V_x = V_0\cos\theta$, and $V_y = V_0\sin\theta$. When I test this with something like 1 m/s and and angle of $45^{\circ}$, I ...
1
vote
1answer
55 views

A ball is dropped from the roof of a building. How fast is it moving after 4.9 seconds? (Absolute value) [closed]

i really need help. A ball is dropped from the roof of a building. How fast is it moving after 4.9 seconds? (Absolute value) in m/s A water balloon is thrown downward from a tall building with an ...
0
votes
1answer
33 views

Horizontal distance covered by an object from an initial height to the ground

We are given: An angle $\theta$ with respect to the ground, its initial height $h_0$ and the final distance $d$. How can we find the initial velocity from this information? I tried a bunch of things, ...
0
votes
0answers
62 views

Projectile under quadratic air resistance force

So here's the problem background: A projectile of mass m is shot straight up with initial velocity $v_0$ and feels a quadratic air resistance force of the form $F = −kv^2$, where $k ≡ mg/u^2$. ($k$ ...
17
votes
5answers
4k views

Is this scene from the A Team explainable by Physics?

This scene (youtube link) from the movie The A-team, the four members are in the tank and its falling from the air, they fire the canon and it slows the tank from falling for a moment before falling ...
1
vote
2answers
120 views

Projectiles Launched at an Angle with unspecified Initial Velocity [closed]

I'm attempting to do my Physics homework, and I did the first one right, but that problem gave me initial velocity. This problem gives me only the angle relative to horizontal and the distance it ...
-2
votes
1answer
42 views

Projectile with air resistance [duplicate]

If you have a projectile with these variables. $x_0 = 1v_{0x} = 70, y_0 = 0, v_{0y} = 80, a_x = 0, a_y = -9.8$ I know how to plot these points with this equation. $$ x = x0 + (v_{0x})t + 1/2((a_x)t^2) ...
1
vote
0answers
60 views

Projectile Motion Equation - Understanding this Formula [closed]

I don't understand why this formula is relevant to the problem: This was the relevant worked solution: My problem is that I do not understand this formula because I don't even understand what ...
0
votes
3answers
97 views

Question on acceleration of gravity

In pre-calculus last week my teacher explained a scenario in which a man throws a rock down a well and takes 4 seconds for you to hear the rock hit the bottom. How far downs the well? Last years I ...
2
votes
1answer
139 views

Add air resistance to projectile motion

I am given an initial x and y position and initial velocity and I was asked to graph the trajectory in 1 second intervals. This is what I have so far: If $x_0 = 1, v_{0x} = 70, y_0 = 0, v_{0y} = 80, ...
0
votes
1answer
42 views

Deviation from 2D trajectory

I need to find out how far a ball is from the predicted trajectory in 2 dimensional space and I know the start and end position of the ball in both dimensions. Along with that I know the initial ...
0
votes
2answers
76 views

Kinematic sign convention

For example, if I drop a ball from a $50$ meters building, then I will consider the ground is $0$ meter downward is positive ( which makes gravity positive, downward velocity positive, etc) so ...
0
votes
1answer
45 views

related to projectile motion [closed]

I was given this worksheet from my teacher and well im finding it really tough so far .. the question below is just crushing my skull .. so i would appreciate it if you guys would guide me through it ...
1
vote
0answers
209 views

What is the angle of projection when at maximum height the speed of a projectile is half the speed at half the maximum height? [closed]

I have been struggling with this problem: The speed of a projectile when it reaches its maximum height is one half of its speed when it is at half its maximum height. What is the initial ...
9
votes
2answers
1k views

Put a bullet into orbit around the moon

While I was watching this beautiful video, the absence of air friction pushed me to ask myself: While standing on the surface of the moon, what is the initial velocity by which you can fire a bullet ...
2
votes
1answer
60 views

Distance along projectile motion [closed]

I was doing kinematics these days, projectile motion. And I did the basic concepts: range, max height, time of flight, projectile on inclined plane. I am curious to know how we would solve a question ...
0
votes
1answer
30 views

Area covered by particle between it's path and horizontal lines

Question: The maximum range of projectile is $R$ and the maximum height attained by the particle is H. If the area covered by the particle between its path and horizontal line is $A$, then ...
-1
votes
2answers
205 views

What strategy should I use to approach this problem? If my straight line approximation doesn't work [closed]

recently i wrote an assignment in one of the questions i got two different answers for the same question by considering a straight line motion The question was somewhat like this THIS IS A HOMEWORK ...
-2
votes
1answer
104 views

How to derive this formula? [closed]

as far as i know the range of an obliquely projected body which is projected with a velocity of u with some angle $\theta$ with the horizontal under the action of gravity is R=$u^2sin2\theta$/g by ...
-2
votes
3answers
190 views

Projectile Motion with air Resistance - Adjust only the Angle to hit a target

OK, let me preface this by saying i am not a physics student, nor have i ever been. I am a software engineer working on a development degree. So this is homework but the assignment was just to create ...
1
vote
0answers
61 views

How to find the force to cause certain trajectory? [closed]

So I got a little board today and decided to do some physics. What I came up with is confusing me alot. Say someone throws a rock and when this happens you get the known's of. From here is there a way ...
1
vote
4answers
104 views

Is it possible to prove that projectiles with drag will not travel in a parabola under the theory of classical mechanics?

Can you prove that projectiles will travel in a parabola, provided the acceleration due to gravity $g$ does not vary significantly along the trajectory? This should take air resistance into account. I ...
0
votes
0answers
28 views

How to calculate the equation of projectile motion for curved ramps? [duplicate]

Consider the following cases (these are sections): I can find the equation of motion for Case a however I don't know how to deal with Case d. Normally I would need the angle α otherwise I can't ...
1
vote
2answers
123 views

Why is the constant velocity model used in a projectile motion derivation?

I was re-studying university physics last week, I'm now in the chapter about kinematics in 2 dimensions and specifically the one treating projectile motion. In page 86 of his book (Serway - Physics ...
0
votes
1answer
62 views

Kinematics and Energy - Finding the work done in projectile motion

If you are asked to find the work done by gravity on a projectile, the force will obviously be the mass multiplied by gravitational acceleration. What will the displacement be, the horizontal or ...
0
votes
2answers
943 views

Kinematics - projectile motion on inclined plane [closed]

Well I've tried everything to solve this problem, spent well over an hour, and have gotten no results. A particle is thrown over a triangle from one end of a horizontal base it grazes the top vertex ...
2
votes
1answer
75 views

Kinematic, motion in 2D [closed]

If the kinetic energy at maximum height is 2/5 the kinetic energy at half the maximum height, find the angle of projection. In other words: K.E. at H(max) = 0.4*K.E. at 0.5*H(max) I got 60 degrees, ...
0
votes
2answers
50 views

Projectile motion - ball hit 180m/s at 45 degrees, what is the hang time? [closed]

Assuming no air resistance etc, how long is the ball in the air for? This is actually part of a longer question concerning the ball trajectory on different planets but I think there must be an easier ...
-2
votes
1answer
166 views

Kinematics - angle of projection given relation between speed at highest point and half of that [closed]

For a projectile launched from a point on horizontal ground, the speed when it is at the greatest height is $\sqrt{\frac{2}{5}}$ times the speed when it is at half of its greatest height. Determine ...
-3
votes
1answer
191 views

Throwing an object in the air [closed]

Studying formulas about velocity and acceleration I came up with a question: if I throw an object in the air with a velocity $v_0$ (suppose i throw it vertically) in how much time its final velocity ...
1
vote
1answer
58 views

Projectile trajectory with linear air resistance [closed]

I have the following equations $$\ x′′(t)=−\frac km x′(t)$$ $$\ y′′(t)=−\frac km y′(t) - g$$ where $k$ is the drag, $m$ is the mass of the object and $t$ is the time. $g$ is the gravity constant. ...
1
vote
1answer
742 views

A ball is thrown up, and a second ball is dropped- what is the maximum initial velocity of the first ball so that

This question only exists in one dimension, the y axis. A ball is thrown upwards with an initial velocity $V_o$ from a roof with height $h$. One second later, a second ball is dropped from the same ...
1
vote
1answer
130 views

Upthrust vs Drag

24: A ball is falling at terminal speed in still air. The forces acting on it are upthrust, viscous drag and weight. What is the order of increasing magnitude of these 3 forces? ...
0
votes
2answers
68 views

When solving kinematics questions, how to find time in air?

I was trying to help a friend with this question: A ball is shot horizontally off a cliff. What would happen to the horizontal distance it travels if the acceleration due to gravity were doubled ...
0
votes
1answer
38 views

Doing a spring experiment, and need to find the stretch required

I'm doing an experiment where I have to calculate the stretch of a spring needed for it to launch itself into a trashcan located some distance away. The spring is located on the edge of a ramp that is ...
0
votes
1answer
49 views

Two equations for $y$ in projectile motions

I have two equations on my equation sheet: $$y=v_o t \sin \theta - \frac{1}{2} g t^2.$$ And then another: $$y_{\max} = \frac{v_o^2 \sin 2 \theta }{2g}.$$ I understand that the first one is an ...
1
vote
1answer
50 views

Minimize initial velocity of projectile to arbitrary point

I'm supposed to shoot a projectile from the origin to a point $(x_0 , y_0)$ with minimal initial velocity $v_0$. (no air resistance; regular gravity) The flight time should be $T=\frac{x_0}{v_x}$. ...
3
votes
0answers
63 views

What is the maximum range of a bullet flying through the sky? [closed]

How far would my bullet fly with the following characteristics? 1.2km/second initial velocity 45 degree angle into the sky 'Normal' atmospheric conditions No wind Typical high-powered rifles have ...