In statistics, a moving average (rolling average or running average) is a calculation to analyze data points by creating a series of averages of different subsets of the full data set. It is also called a moving mean (MM) or rolling mean and is a type of finite impulse response filter. Variations include: simple, cumulative, or weighted forms (described below).
Given a series of numbers and a fixed subset size, the first element of the moving average is obtained by taking the average of the initial fixed subset of the number series. Then the subset is modified by "shifting forward"; that is, excluding the first number of the series and including the next value in the subset.
A moving average is commonly used with time series data to smooth out short-term fluctuations and highlight longer-term trends or cycles. The threshold between short-term and long-term depends on the application, and the parameters of the moving average will be set accordingly. For example, it is often used in technical analysis of financial data, like stock prices, returns or trading volumes. It is also used in economics to examine gross domestic product, employment or other macroeconomic time series. Mathematically, a moving average is a type of convolution and so it can be viewed as an example of a low-pass filter used in signal processing. When used with non-time series data, a moving average filters higher frequency components without any specific connection to time, although typically some kind of ordering is implied. Viewed simplistically it can be regarded as smoothing the data.
Homework Statement
a 2 kg softball is pitched to u at 20 m/s. you hit the ball back along the same path, and at the same speed. IF the bat was in contact with the ball for 0.10 s, what is the magnitude of the average force the bat exerted?
Homework Equations
FAT=Pf-pi
The Attempt...
Homework Statement
After falling from rest at a height of 29.8 m, a 0.422 kg ball rebounds upward, reaching a height of 21.7 m. If the contact between ball and ground lasted 1.83 ms, what average force was exerted on the ball?
Homework Equations
Change in momentum (p) = Fnet* Change in...
Homework Statement
A stream of water strikes a stationary turbine blade, as the drawing illustrates. The incident water stream has a velocity of +18.0 m/s, while the exiting water stream has a velocity of -18.0 m/s. The mass of water per second that strikes the blade is 75.0 kg/s. Find the...
A 1900 kg car moving at 20.0 m/s crashes into a brick wall and is stopped. The driver's mass is 70.0 kg, and although the driver is not wearing his seatbelt, the air bag thankfully slows him to a stop in 0.100 s. What is the magnitude of the average force that the air bag exerts on the driver...
Homework Statement
A golf ball of mass 41.8 g is dropped from a height h = 1.41 m onto a hard floor and bounces back to exactly that same height. What is the average force (in N) on the ball during the 0.012 s that it was in contact with the floor?
Homework Equations
Impulse = Ft...
Homework Statement
A 0.140-kg baseball traveling 45.0 m/s strikes the catcher's mitt, which, in bringing the ball to rest, recoils backward 11.0 cm. What was the average force applied by the ball on the glove?
Homework Equations
F=ma ?
The Attempt at a Solution
It is the whole...
I can't seem to master this equation, because I think I'm doing things right and I'm not.
Homework Statement
When a 410 baseball gram is hit, its velocity changes from +28.87 m/s to -22.34 m/s. The baseball is in contact with the bat for 56.10 milliseconds. You may assume that the balls...
1. A 9800kg rocket is traveling east along a horizontal frictionless rail at a velocity of 11m/s. The rocket is then accelerated uniformly to a velocity of 22m/s in a time of 0.75s by the expulsion of hot gases. What is the average force at which the gases are expelled by the rocket...
Homework Statement
A 1.83 kg steel ball strikes a massive wall at
4.08 m/s at an angle of 67.6◦ with the plane of
the wall. It bounces off with the same speed
and angle. If the ball is in contact with the wall for
0.105 s , what is the magnitude of average
force exerted on the ball by...
Homework Statement
Estimate the average force exerted by a shot-putter on a 7.5 kg shot if the shot is moved through a distance of 3.0 m and is released with a speed of 11 m/s.
Homework Equations
F=ma
using cos and sin?
The Attempt at a Solution
not sure how to begin
Homework Statement
A 1150kg airplane starts from rest and accelerates forward for 7.3 seconds until it reaches its takeoff speed of 31m/s. What is the average force on the airplane during this time?
I tried F= ma, but I get a number that is far too large.
F= 1150kg times (31/7.3) = 4883.6N I...
Homework Statement
A 0.140-kg baseball traveling 33.0 m/s strikes the catcher's mitt, which, in bringing the ball to rest, recoils backward 13.0 cm.
What was the average force applied by the ball on the glove?
Homework Equations
F=\DeltaM/\DeltaT
The Attempt at a Solution
I don't...
A tennis ball has a mass of 0.057 kg. A professional tennis player hits the ball hard enough to give it a speed of 44 m/s (about 99 miles per hour.) The ball moves toward the left, hits a wall and bounces straight back to the right with almost the same speed (44 m/s). As indicated in the diagram...
Homework Statement
A 300kg block is suspended by a cable.
a) what is the weight of the motor block?
b) the cable snaps and the block falls 3 metres to the ground below.
i) calculate the time taken for the block to reach the ground.
ii) calculate the impact velocity of the block with...
Homework Statement
A proton with mass 1.67 X 10-27 kg that has a speed of 5.0 x10[6] m/s passes through a metal film of thickness .010 mm and emerges with a speed of 2.0 x 10[6]m/s. How large an average force opposed its motion through the film?
Homework Equations
I'm thinking Newtons...
Homework Statement
An Airplane is traveling at 225 m/s when it strikes a weather balloon (m=1.82 kg) which can be considered to..?
be at the rest relative to the ground below. After the collision, the balloon is caught on the fuselage and is traveling with the airplane. The collision takes...
Homework Statement
A 2.18 kg steel ball strikes a massive wall at 12.6 m/s at an angle of a = 55.1o with the plane of the wall. It bounces off with the same speed and angle (as seen in the figure below). If the ball is in contact with the wall for 0.152 s, what is the average force exerted...
A proton (m=1.67x10^-27 kg) that has a speed of 5.0x10^6 m/s passes through a metal film of thickness 0.010mm and emerges with a speed of 2.0x10^6 m/s. How large an average force opposed its motion through the film??
can anybody give me a clue on where i can start?
A woman with a mass of 44 kg runs at a speed of 8 m/s and jumps onto a giant 30 kg skateboard initially at rest. What is the combined speed of the woman and the skateboard?
44 kg / 8 m/s=5.5
30 kg / 8m/s=3.75
5.5+3.75=9.25m/s
[solved]Average force exerted on object by wall
Handball
A 301.0 g handball moving at a speed of 5.3 m/s strikes a wall at an angle of 29.0° to the normal of the wall and then bounces of with the same speed at the same angle. It is in contact with the wall for 0.002 s. What is the average...
Homework Statement
Two bodies A and B collide in a totally inelastic collision. Using the relevant equations and given that the mass of body A is 1200kg and the collision lasts for 0.2s, determine the average force vectors acting on each body during the collision.
Homework Equations...
Homework Statement
1. A 300g handball moving with a speed of 5 m/s strikes the wall at an angle of 40 degree and then bounces off with the samw speed at the same angle. It is in contact with the wall for 2ms. What is the average force exerted by the ball on the wall ??
2. A handball of...
Homework Statement
A 6 kg steel ball strikes a wall with a speed of 11.2 m/s at an angle of 50.5 degrees with the normal to the wall. It bounces off with the same speed and angle. If the ball is in contact with the wall for .219s, what is the magnitude of the avg force exerted on the ball by...
Homework Statement
A 1200 kg car drives headlong into a brick wall at 14 m/s and rebound at 3 m/s. The collision lasts for .10 seconds. What is the average force on the car during the collision?
Homework Equations
F=ma
f*change in time= mass * change in velocity
f= mass*change in...
Homework Statement
A 0.43 kg piece of putty is dropped from a height of 2.8 m above a flat surface. When it hits the surface, the putty comes to rest in 0.22 s. What is the average force exerted on the putty by the surface?
Homework Equations
F\Deltat=\DeltaP
F\Deltat=mvf-mvi...
A 425 g ball with a speed v of 6.5 m/s strikes a wall at an angle of 30° and then rebounds with the same speed and angle. It is in contact with the wall for 9.0ms. (a) What is the impulse on the ball (take positive as down in the figure)?
b. What is the average force exerted by the ball on...
Homework Statement
A ball of mass 1.5 kg is traveling downward at a speed of 10 m/s. It comes to rest in your hand in .25 s. What is the net impulse exerted on the ball? What is the average force exerted by the hand on the ball (Don't forget the gravitational force.)
Homework Equations...
Homework Statement
A ball of mass 200 g is released from rest at a height of 2.00 m above the floor and it rebounds straight up to a height of 0.900 m. (a) Determine the ball's change in momentum due to its contact with the floor. (b) If the contact time with the floor was 0.0950 seconds, what...
A 60g handball moving with a speed of 5m/s strikes the wall at a 40 degree angle with the norm, and then it bounces off with the same speed at the same angle with the norm. It is in contact with the for 2.0ms.
a)What is the average force exerted by the ball on the wall?
b)The rebounding...
A 68 kg man drops to a concrete patio from a window only 0.60 m above the patio. He neglects to bend his knees on landing, taking 2.0 cm to stop. What is the magnitude of the average stopping force?
-From this problem I have already found that the average acceleration is 293.95 m/s^2. I tried...
A fire hose sprays 450 liters of water a minute onto a fire with a velocity of 17.0 m/s. Water has a density of 1 kg/liter. What is the average force acting on the fireman holding the hose due to the water?
Is it just:
F=pt
F=450*17.0*60
F=459000N
The force seems kind of big?
Homework Statement
A 3.00 kg stell ball strikes a wall with a speed of 9.0m/s at an angle of 60° with the surface. It bounces off with the same speed and angle. If the ball is in contact with the wall for .200 s, what is the average force exerted by the wall on the ball?
Homework...
Superman leaps in front of Lois Lane to save her from a volley of bullets. In a 1 minute interval, an automatic weapon fires 149 bullets, each of mass 8.0 g, at 430 m/s. The bullets strike his mighty chest, which has an area of 0.74 m2. Find the average force exerted on Superman's chest if the...
[SOLVED] Average force of air resistance
In early test flights for the space shuttle using a "glider" (mass of 1500kg including pilot), it was noted that after a horizontal launch at 750km/h at a height of 4500m, the glider eventually landed at a speed of 300km/h. What would it's landing speed...
A tennis ball may leave the racket of a top player on the serve with a speed of 62.0 m/s. If the ball's mass is 0.0600 kg and it is in contact with the racket for 0.0200 s, what is the average force on the ball?
I need help with this problem. I have no idea how to start it
A baseball that weighs 140 g and is traveling at 30 m/s moves a fielder's glove 35 cm backward when the ball is caught. What was the average force exerted by the ball on the glove.
Thanks in advance
[SOLVED] Formula for average force?
In a ballistics test at the police department, Officer Rios fires a 6.0 g bullet at 350 m/s into a container that stops it in 1.8 ms. What is the average force that stops the bullet?
can anyone help me to do this? or just give me the formula? The teacher...
Homework Statement
http://img88.imageshack.us/img88/9351/springny2.jpg [/URL]
Homework Equations
E_p = \frac{Fx}{2}
E_k = \frac{mv^2}{2}
The Attempt at a Solution
http://img231.imageshack.us/img231/4773/worknd6.jpg [/URL]
I get 2.22 m/s, but the answer key says 3.1 m/s. Where did...
Average force is change in momentum, divided by change in time, correct?
So when I land on the ground after jumping, how can I calculate the average force I exert on the ground, (while I decelerate from velocity at moment I touch ground to zero velocity).
I calculated my velocity just when...
Homework Statement
A 4.00 kg steel ball is dropped onto a copper plate from a height of 10.0 m. If the ball leaves a dent 2.75 mm deep, what is the average force exerted by the plate on the ball during the impact?
Homework Equations
KE=1/2mv^2
F=ma
Wgrav=mgh
The Attempt at a...
Homework Statement
a 8kg steel ball strikes a wall with a speed of 11.7 m/s at an angle of 35.3 degrees with the normal to the wall. it bounces off with the same speed and angle as shown in the picture.
http://img405.imageshack.us/img405/7733/asdfkf7.jpg
If the ball is in contact with...
Homework Statement
A bullet, having a mass of 18g and traveling with a velocity of 1200 m/s strikies a wooden block and pentrates 2.5m. What is the average force exerted by the block on the bullet?
Homework Equations
W= F*total distance
W= .5*m*V2^2 - .5*m*V1^2
The Attempt at a...
A 57.0 kg person jumps from rest off a 11.0 m high tower straight down into the water. Neglect air resistance during the descent. She comes to rest 3.00 m under the surface of the water. Determine the average force that the water exerts on the diver. This force is nonconservative.
i know to...
Homework Statement
During an autumn storm, a 0.012 kg hail stone traveling at 20 m/s made a .20 cm deep dent in the hood of a person's car. What average force did the car exert to stop the damaging hail stone?
Homework Equations
d = vt
ft = mv
The Attempt at a Solution
Vav =...
Homework Statement
Auto companies frequently test the safety of automobiles by putting them through crash tests to observe the integrity of the passenger compartment. If a 1000. kg car is sent toward a cement wall with a speed of 14 m/s and the impact brings it to a stop in 8.00 * 10^-2...
Homework Statement
A 59.8kg ice skater, moving at 14 m/s crashes into a stationary skater of equal mass. After the collision, the two skaters move as a unit at 7 m/s. Suppose the average force a skater can experience without breaking a bone is 4640N. If the impact time is 0.047s, what is the...
[SOLVED] Calculate Average Force by finding Impulse over Impact Time
Homework Statement
A movie depicting a 55-g golf ball hit with a club shows that the impulse time between the club and the ball is 0.2 ms, and the initial speed of the ball is 136 mph.
a) What is the average force exerted...
i don't understand wat I am doing wrong here is my problem
Choose the positive direction to be
from the pitcher to the plate (some answers
may be negative).
A pitcher throws a 0.13 kg baseball so that
it crosses home plate horizontally with a speed
of 31 m/s. It is hit straight back at the...
Homework Statement
0.15 kg baseball is pitched with a speed of 36 m/s (79.2 mph). When the ball hits the catcher's glove, the glove moves back by 4.9 cm (1.96 in.) as it stops the ball.
(a) What was the change in momentum of the baseball?
5.4 kg·m/s opposite the ball's direction of...