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Velocity

Velocity is the rate of change of the position of an object. It is equivalent to the speed and direct of motion. Speed is a scalar quantity whereas velocity is a vector quantity. Velocity gives the magnitude and direction of motion. For example, if a car is moving at 100 km/h to the west, the velocity has been specified. If the velocity is constant, the object has a constant speed in a constant direction.

There are many equations of motion to calculate velocity.

v= Δx/Δt (1)

v=u+aΔt (2)

v^2= u^2+2aΔx (3)

Velocity can also be two-dimensional and expressed in polar coordinates. With polar coordinates, there are two types of velocity, radial and angular velocity. Radial velocity is the component of velocity away from or towards the origin. The angular velocity is the rate of rotation about the origin. The transverse velocity is the component of velocity along ta circle centered at the origin. The equation of velocity in a polar coordinate system is:

v=v_T+ v_R (4)

The magnitude of the radial velocity is a dot product. The equation is as followed:

v_R= (v*r )/(|r|) (5)

Where r is the displacement.

Categories within Velocity

Periodic Motion

Postings: 121

Periodic motion is motion repeated at equal intervals of time.

Determining Initial Velocity

In a baseball game a base-runner can attempt to advance when a fielder catches a hit ball before it reaches the ground, so long as the runner doesn't leave base before the fielder catches the ball. The fielder then attempts to throw the ball to the base ahead of the runner. If a base-runner can run from 3rd base to home plate in

Finding the moment of inertia

A sheet of plywood 1.37 cm thick is used to make a cabinet door 50.9 cm wide by 76.9 cm tall, with hinges mounted on the vertical edge. A small 191-g handle is mounted 45 cm from the lower hinge at the same height as that hinge. If the density of the plywood is 550 kg/m^3, what is the moment of inertia of the door about the hing

Physics Problems: Velocity, Impact, Speed

a) Mr. Stick lives on the planet Teflon where the force due to gravity is different than that of Earth. Mr. Stick drops a small water balloon off the top of a building (V0 = 0 m/s). He releases the balloon at a height H = 10 m above the surface of Teflon. The balloon hits the ground 1.8 seconds after it is dropped and has a velo

Modelling Projectile Motion Problem

Modelling problem - Plan the solution by set up equations and - Execute & Evaluate = do the problem, state the answer & INCLUDE UNITS!!! A football is kicked across a level field. The ball spends 3 seconds in the air and lands 60 m from the point where it was kicked. (Ignore air resistance). a) What is the speed of the

Finding Overall Speed and Velocity

Each of parts (b), (c) and (d) requires you to use numerical answers found in earlier parts of the question. A dragonfly has a flight speed in still air of 4.5ms-1. It is pointed in the direction N - 29 degree - E, but flies in a wind of speed 7.5ms-1 from the direction S- 42 degree - E. Take i to be 1ms-1 due east and j to

Summary of kinematics, solutions to kinematics problems.

Here, we provide a brief summary of some common kinematics, and solve three common kinematics problems, specifically from College Physics, by J. Serway, et al. We specifically find: For a car traveling east at a given velocity, the final velocity for a constant acceleration in two different directions. For an arrow shot s

Group velocity of localized waves

Section 2-2 discusses the superposition of two classical sinusoidal waves of slightly different wave numbers k and k+[delta]k to yield a modulated result whose modulations move with a group velocity. A composition almost as simple as the two-component case is the superposition of three waves y_0, y_1, and y_2 with the same tota

Speed and Momentum Calculations

A pitcher claims he can throw a 0.168 kg baseball with as much momentum as a 3.32 g bullet moving with a speed of 1.21584x10^5 m/s. What must be its speed if the pitcher's claim is valid? Answer in units of m/s. This is an "explosion" question. A 30-06 caliber hunting rifle fires a bullet of mass 0.0115 kg with a velocity of

Physics Practice Test: Tension, Acceleration, Velocity Etc.

See the attached file. 1. A plane leaves the airport and flies east at 109 miles/hour. 4.5 hour(s) later a second plane leaves east at 240 miles/hour. How long after taking off does the second plane overtake the first plane? 2. What is the tension on an elevator cable if the elevator (with a mass of 1209.3 kg) is traveling

Velocity Algorithm Code

Write the simplest possible one-dimensional "molecular dynamics code" for two particles. I used matlab, so i need matlab code for molecular dynamics or velocity verlet algorithm code. I need to determine x1, x2 and v1, v2 in different time steps. I have the following 15 values for x1, x2 and v1,v2 in graphs: M = 1.0 d

Cannon Ball Trajectory

A canon ball with mass m has a mechanism that blows it into 4 pieces of equal mass, who spread (relative to the canon ball with no motion) at 90 angles: forward, backwards, down, up in equal velocities. The canon ball is being fired from a canon at velocity V and angle of 45 degrees above the horizon, and it spreads at the ma

Molecular Dynamics MATLAB Code

Write the simplest possible one-dimensional "molecular dynamics code" for two particles? I use MATLAB, so I want a MATLAB code for molecular dynamics or velocity verlet algorithm code. I need to determinate x1, x2 and v1, v2 in different times. Some websites may help you: [http://www.nada.kth.se/~tomaso/miklab2007/lab2_4h

Vectors and Velocity Problem

I need a perfect step by step solution of the following problem: A particle of charge q is started at the origin with an initial velocity (vector)v_0 = v_0 x(^), in a region where a uniform electric field exists (vector)E = E_0 z(^), and a magnetic field intensity is given by (vector)B = B_0 x(^) + B_0 y(^). HINT: ROTATE TH

Using the Difference Quotient to Calculate Average Velocity

A ball is released at the top of a ramp (an inclined plane). The distance it travels can be expressed as the function: s(t)=5t^2, where t is the time in seconds after the ball is released. The distance function, s(t), is measured in feet. Find the average velocity of the ball for the time interval [1,4].

The Effect of Height on a Normal Force

Sarah Jane Smith rides a friction less roller coaster with an initial hill height H (on top of which the car is barely moving. At the bottom, where the track has a radius of curvature R, the car has a speed V and she feels 25% heavier than her actual weight (that is, Fn = 1.25 Fg, where Fn is the normal force the seat exerts on

What speed does a truck hit a tree

The driver of a truck comes suddenly upon a fallen tree that has blocked the road ahead. A total time interval of 5.45 seconds elapses during which the driver recognizes the hazard, determines the need to brake, hits the pedal, and ultimately slams into the tree. The driver's reaction time uses the first 1.25 seconds of the to

Impulse-Momentum Theorem of a Bullet

A gun fires a bullet of mass 17 grams out of a barrel 24 cm long. The bullet is accelerated down the length of the barrel with an average force of 16 Newtons. Using the Impulse-Momentum Theorem, determine the velocity with which the bullet exits the barrel. What average force is exerted by the individual holding the gun

Kinematices - Position versus Time Graphing

For each region shown below a - g, draw a section of a position versus time graph that corresponds to the regions written description (a) - (g). Assume that moving to the right is AWAY from the starting point and moving to the left is TOWARDS the starting point.

Instantaneous velocity of the object

Please help with the following problem. Please provide step by step calculations. Consider a moving object whose displacement at time t is given by s(t)=â?'5t^(2)+3t. We will take steps to find the instantaneous velocity of the object at time t=9. (a) For any time t [cannot]= 9 the average velocity of the object on

Kinetic energy of a body of mass; Vertical motion

22. a) A 200kg car is traveling 22 m/s. Find the kinetic energy in Joules. b) The same car is lifted vertically upward and then dropped from rest. Find the height from which it is dropped if it strikes the ground at 22 m/s (neglect air resistance). 23. In a movie, a monster climbs to the top of a building 30 m above the groun

Determine the relative and absolute velocity and acceleration

Figure in the attachment shows an arrangement of a carriage system. A force P is applied on the carriage B, moving rightward at 3 m/s^2 constant acceleration. At the instant shown the velocity of B is 2 m/s. (i) Determine the velocity of B relative to A. (ii) Determine the acceleration of B relative to A. (iii) Determine th

Determine the distance when the ball is struck again

A ball of mass 150 g is fired from a smooth 30 degree incline at an angle theta with the incline as shown in the figure in the attachment. The initial velocity of the ball is v0 = 10 m/s. It travels after struck by the ground with the velocity v2 as shown. If the coefficient of restitution between ball and ground is 0.75, determ

Force and work, Work-Energy Theorem, Gravitational Energy, Conservation

Conceptual Questions: **Please consider significant figures and if possible, draw visual graphics** Two forces F1 and F2 are acting on the box showing in the drawing (sorry, I don't know how to draw the angle θ between the 2 lines!), causing the box to move across the floor. The two force vectors are drawn to scale. Which fo

motion of projectile

Please see attached form. Show all work. 1. An object is thrown vertically upward with an initial velocity v0. At the highest point in the object's trajectory: a. its velocity and acceleration are both zero. b. its velocity and acceleration are both nonzero. c. its velocity is zeor, and its acceleration is nonzero and dire

Velocity and Acceleration of a Freely Falling Ball

I constructed a fairly simple experiment related to curvlinear motion. The experiment involved a small metal ball that rolls off a table and lands on the floor. I used the edge of table as the Y direction. I timed the trial run from the of the edge of the table and when the ball hits the floor. I know X (total of all time thr

Terminal velocity of pilot; ideal pulley; pop gun's spring

1. In 1955 a pilot fell 370 meters without his parachute opening. He landed in a snowbank, making a crater 1.1 meters deep. He walked away with minor injuries. If his mass was 80 kg and his terminal velocity was 35 m/s, calculate a) the work done on him by the snow b) the average force exerted on him by the snow c) the wor

Create an experiment that relates to curvilinear motion

I need help with a simple experiment. I'm trying to create an experiment that relates to curvilinear motion. However, I'm unsure how to set up an experiment and show all the calculations. Can someone help me with creating a simple experiment to show what curvilinear motion is and do those calculations I can make up the data

Mechanics: Problems and Solutions

1. A projectile of mass 0.6 kg is fired vertically upwards in the barrel of a gun by a vertical net propelling force of 50 N acting over a period of 0.5 seconds. Calculate: (a) The velocity of the projectile when it leaves the gun. (b) The height reached by the projectile. (c) The time taken from the projectile leavin