Balls Definition and 555 Threads

Homework Statement Two students conduct physics experiments on a balcony 19.6 m above the street. One student throws a ball vertically downward at 14.7 m/s. At the same instant the second student throws a ball vertically upward at the sam speed. The second ball follows the same path as the...

Homework Statement A red ball is thrown down with an initial speed of 1.2 m/s from a height of 25 meters above the ground. Then, 0.6 seconds after the red ball is thrown, a blue ball is thrown upward with an initial speed of 23.8 m/s, from a height of 0.8 meters above the ground. The force...

Homework Statement So, I am having trouble trying to understand my results. The experiment was marble (1.5cm & 5gram) was dropped on the surface of water, in a 40 cm cylindrical tube roughly 4cm diameter. The graph is negative, since the I used a program to analyse the velocity. Homework...

Hi! Here is my task: There are 5 white and 5 black balls in box. Two balls at the time are extracted from box. Let random variable X be "number of extractions of balls with same colour. Find probability of random variable. x can go from 0 (5 times we extract two by two balls and they are with...

I found this picture somewhere: My question being, as in the picture, which ball gets to the end faster? I guess you could naively say that ball A reaches the end in less time, but then again, there is the force of gravity which would accelerate the ball going downwards (and deaccelerate it...

Hi! Here is my task: There are 4 white and 6 red balls in array. Find probability that there are three white balls in beginning of array. How to calculate m?

Hi I had a question based on inertia if two balls one heavy and one light are on a bus which is moving with velocity v and the bus stops, which ball will move faster and why?

We have had a heated debate at work and I feel we need to bring in a few outsiders into help clear things up. A co-worker of mine believes that if you had a string of bucky balls (small spherical neodymium magnets) held by only the top ball in the chain and allowed to hang such that you could...

Homework Statement Ball A is thrown straight upward and returns to its original level in 2 seconds. Ball B is thrown at a 40 degree angle above the horizontal and also returns to its original level in 2 seconds. What is the initial speed of each ball. Homework Equations ΔV=at...

A box contains 2 red, 4 white, and 4 green two balls are drawn in succession without replacement. What is the probability that both balls are the same color?

Two balls, each of mass 0.50g are each suspendedd from an insulating thread 1.0m long. The upper ends of the threads are attached to the same point. When the balls are equally charged they repel each other and are in equilibrium when they are 30cm apart. Find the charge on the two balls. F =...

Suppose I have an box (set) containing two different colored balls, red and blue, say. Now, suppose the balls differ in size, where the size of the red balls has one particular distribution and those of the blue another. How can we describe the distribution of the balls in the box?

Hey! (Giggle) I am given this exercise: If we have a pile of infinite balls and $n$ numbered boxes with a capacity of $n$ balls each one,with how many ways can we place some balls in the boxes?Answer the same question,if the boxes are not numbered. Could you give me a hint what to do...

Homework Statement A bag contains n identical red balls, 2n identical black balls and 3n identical while balls. If probability of drawing n balls of same color is greater than or equal to 1/6, then minimum number of red balls in the bag is equal to?The Attempt at a Solution P =...

Lycra sheet + support + massive balls = "Gravity Visualized" Neat "rubber sheet" analogy of the curvature of space time on YouTube. Skip to 5:57 for orbits around the Earth moon system if you don't have time to see the whole thing. Would have been nice to see that demo as a kid. Url of...

Greetings, I was thinking about bouncing a tennis ball against a wall and how its momentum and kinetic energy would change. I asked a friend of mine and he answered that the ball would transfer more forward momentum than it had to the wall but its kinetic energy would remain constant. How is...

Homework Statement Emil and Kerry are standing on a stationary cart with frictionless wheels. Total mass of cart and riders is 130 kg. At the same instant, Emil throws a 1.0 kg ball at 4.5 m/s to Kerry while Kerry throws a 0.5 kg ball to Emil at 1.0 m/s. Emil's throw is to the right and...

Hi, I am wondering if total momentum of the system is conserved in this case. Our system is consisted of two balls: one is falling vertically down to ground, another is thrown vertically up, so they collide in air. Is total momentum of the two balls conserved after the collision? Now I...

Introduction: This isn't really a homework question in that I recently came across Feynman's original problem sets that had accompanied his famous lectures of 1960 and decided to solve them (and I've been doing rather badly). But at some point, I figured it would fall into this category best...

Homework Statement A 0.50 kg ball with a speed of 1.5 m/s in the positive direction has a head-on elastic collision with a stationary 0.80 kg ball. What are the velocities of the balls after the collision? Homework Equations I've used the Ek = (1/2)m(v^2) so far. The Attempt at a...

Hello everyone, I'm trying to find the exact velocities of three balls in the plane after they collide elastically. I'm assuming arbitrary positive masses and arbitrary positive radii. Of course, three balls can collide in many ways: in an equilateral triangle: one coming from north, one...

Homework Statement Two small .1 gram stryofoam balls are strung like beads on a vertical insulating thread. The lower ball is glued to the thread but the upper ball is free to move. Imagine that both are given an equal amount of negative charge such that the upper ball is suspended about the...

Homework Statement Two identical steel balls,each of diameter 25.4mm and moving in opposite directions at 5m/s,run into each other head-on and bounce apart.Prior to the collision,one of the balls is squeezed in a vise while precise measurements are made of the resulting amount of...

A surprising find looking for something else: http://www.physics.usyd.edu.au/~cross/ Somewhat extensive notes on various small-ball sports physics - including material on collision physics and a neat vid of a falling slinky. I've mined: Ball bounce for comparative data for experiments...

Homework Statement A ball with an initial speed of v1 = 21.5 m/s collides elastically with two identical balls whose centers are on a line perpendicular to the initial velocity and that are initially in contact with each other. The first ball is aimed directly at the contact point and all...

Homework Statement Two identical balls, their centers 24.0cm apart, experience a mutual gravitational force of 5.3×10−6N .Find the ball's mass de Homework Equations F=Gm1m2/r^2 Isn't this just backwards? 5.3x10^-6=(6.67x10^-11)(m^2)/24^2 6765.28kg? that wasn't right i thought it may be in g...

I'm just wondering: in the case when there is 3 balls and ball 2 and ball 3 is stationary. Ball 1 hits ball 2 then stops and ball 2 hits ball 3. Ball 2 moves at an angle of let's say 30 degrees to the left and ball 3 moves at an angles of 60 degrees to the right. You then combine the vectors to...

Hello! I'm hoping someone or group of someones can help me with something I'm stuck on, having to do with the Michelson Morley Experiment (MME for short if that's okay). I want to say that I'm learning Relativity and I'm getting it, as long as I accept the Given that the speed of light will...

Homework Statement Three identical small balls of mass m with uniformly distributed charge Q each hang from a string of length L. The strings are all tethered at the opposite end at the same point. (a) Find the general equation for the angle θ of each string from vertical. Homework...

Homework Statement 17 balls named LOSE 3 balls named WIN no replacements person who selects 3rd win ball wins the game, regardless of who selected the other 2 WIN balls a)If i draw 1st, find the probability that I win the game on my second draw b) If I draw 1st, find the probability...

I have 2 interesting questions, I believe, regarding polymer properties. I am designing a ball (pretty much like a basketball in size and appearance) to be used inside pressure vessels for certain corrosive fluids. The ball is inflated with air to a certain pressure in order to cushion extreme...

Homework Statement Two balls collide on a frictionless surface. Mass m1 = .4 kg and Mass m2 = .3 kg . The initial velocity of m1 is 3 m/s. While m2 is at rest. After the collision the velocity of m1 is 1.5 m/s, θ1 above the horizontal. While m2 gains an unknown velocity of v2f, θ2 below the...

Homework Statement A tennis ball is a hollow sphere with a thin wall. It is set rolling without slipping at 4.08 m/s on a horizontal section of a track as shown in the figure below. It rolls around the inside of a vertical circular loop of radius r = 45.8 cm. given radius =0.458m ω= 4.08...

Hello all, I am attempting to simulate collisions of pool balls. For the moment i am doing so without taking rotational momentum or friction between balls into account. right now i have a system that successfully simulates a collision between 1 ball and another ball. Here's how it basically...

Homework Statement A ball A is dropped from rest from a height of 2.0 m above the floor. Meanwhile that ball A is released, an other ball B is pushed away with the starting speed v_0 from the position shown in Figure. Which angle α is needed for B to collide with ball A? Homework...

Hey! I need some help at the following exercise... We have a box with balls and 10% of them are red. If we choose at random 20 balls with replacement, which is the probability to pick more than 3 red balls? Thanks in advance!

Hi, if in an urn there are 3 red balls and 2 white balls and we draw 2 balls from the urn without replacement. If we assume that at each ball in the urn is equally likely to be chosen, what is the probability that both balls are red? I know the solution is \frac{\binom{3}{2}}{\binom{5}{2}}...

This is from an old course I took. I'm not sure what I'm doing incorrectly. Homework Statement Two identical bowling balls are rolling on a horizontal floor without slipping. The initial speed of both balls is V = 9.9 m/s. Ball a encounters a frictionless ramp, reaching a maximum height...

we have numbered balls in a bag from 1 to 10. We put our hand and take one. Let the number of X be the first number of the ball. Replace the ball into the bag again and takes another ball at random. Let the number of Y the number of the second ball. IF Z =max{X, Y}. we want to find P(Z=9)...

Homework Statement Please open the attachment for the question Homework Equations 1)coulomb's law The Attempt at a Solution I'm at a loss regarding what to do. Upon reading the question (ignoring the figure), I assumed that the charges will form a square and thus the angle between...

Basic problem: Urn I has 4 white and 4 black balls. Urn II has 2 white and 6 black balls. Flip a fair coin. If the outcome is heads, then a ball from urn I is selected, whereas if the outcome is tails, then a ball from urn II is selected. Suppose a white ball is selected and the replaced. Denote...

Hello, I am reading through the problem given in this link: http://physicstasks.eu/uloha.php?uloha=300 There is one sentence I am particularly unsure of, "Charged ball's potential is in direct proportion to the charge of the ball and in reciprocal proportion to the ball's radius." Why is this...

Homework Statement Two balls are thrown vertically upward, one with an initial speed twice that of the other. The ball with the greater initial speed will reach a height - twice that of the other - 4 times that of the other Homework Equations dy = vt + 1/2 at^2 [if i use this equation, i...

Homework Statement Two very small metal coated foam spheres, each of mass 2.80x10^-6kg, are attached to nylon threads 45cm long and hung from a common point. When the spheres are given equal quantities of negative charge, each supporting thread makes an angle of 15 degrees with the vertical...

Probability Question -- colored balls in 2 bowls -- Baye's formula? Bowl #1 contains 2 red balls and 2 white balls Bowl #2 contains 3 red balls and 2 white ball one bowl is chosen at random (each is equally likely) (A) What is the probability of choosing a red ball? Let R stand for...

Problem: In beginning mechanics physics labs, it is very often the case that you get large experimental error. This can be due to a number of factors, friction, of course, being a major player. However, it can also be the case that you might be comparing apples to oranges. For example, if you're...

Homework Statement A ball is thrown straight up from the edge of the roof of a building. A second ball is dropped from the roof 1 second later. You may ignore air resistance If the height of the building is 20m what must the nitial speed of the first ball be if both are to hit the ground...

Homework Statement 12. You are given a large collection of identical heavy balls and lightweight rods. When two balls are placed at the ends of one rod and interact through their mutual gravitational attraction (as is shown on the left), the compressive force in the rod is F. Next, three...

Hello, everyone! I'm conducting an experiment in a lab and while setting parameters, this question came to my mind. Are ping-pong balls hydrophobic? (They are made out of cellulose) And if sesame oil or grease is coated on the surface, do they become hydrophobic? Thanks, as always :approve:

Homework Statement A juggler performs in a room whose ceiling is 3m above the level of his hands. He throws a ball upward so that it just reaches the ceiling. a) What is the initial velocity of the ball? b) What is the time required for the ball to reach the ceiling? At the instant when the...