The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object's speed and direction of motion (e.g. 60 km/h to the north). Velocity is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of bodies.
Velocity is a physical vector quantity; both magnitude and direction are needed to define it. The scalar absolute value (magnitude) of velocity is called speed, being a coherent derived unit whose quantity is measured in the SI (metric system) as metres per second (m/s or m⋅s−1). For example, "5 metres per second" is a scalar, whereas "5 metres per second east" is a vector. If there is a change in speed, direction or both, then the object has a changing velocity and is said to be undergoing an acceleration.
Hello. I was doing some physics and I came across a problem involving gravity.
The problem was finding out how long (in disregaurd to atmosphere) long (time) it would take for a body to reach earth. I'm familiar with distance's derivatives, which give me:
t=\sqrt{\frac{2D}{g}}
where t=time...
Homework Statement
You have determined the acceleration a_{i} of an object in free fall for i = 1 to n different time intervals. What is the algebraic expression for the uncertainty σ_{a,avg} in a_{avg}? (Use any variable or symbol stated above as necessary.)
The answer box is formatted as...
At a certain time a particle had a speed of 11 m/s in the positive x direction, and 1.3 s later its speed was 78 m/s in the opposite direction. What was the average acceleration of the particle during this 1.3 s interval?
Homework Equations
I have Vi=11m/s, Vf=78m/s and t=1.3 m/s
The...
Homework Statement
"A bullet is fired through a 5.0 cm thick board of some material. The bullet strikes the board with a speed of 200 m/s, and emerges out the other end at 100 m/s.Homework Equations
a= (change in velocity)/(change in time)
average velocity = .5(initial v + final v)The Attempt...
Homework Statement
Starting from rest, a subway train first accelerates to 25m/s and then begins to brake. Forty-eight seconds after starting, it is moving at 17 m/s. What is its average acceleration in this 48-s interval?
Homework Equations
1. v=v0+at
2. x=x0+(1/2)(v0+v)t
3...
Homework Statement An object traveling at a constant velocity v0 experiences a constant acceleration in the same direction for a period of time t. Then, an acceleration of equal magnitude is experienced in the opposite direction of v0 for the same period of time t. What is the object's final...
A 52.0-g Super Ball traveling at 28.0 m/s bounces off a brick wall and rebounds at 16.5 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 3.60 ms, what is the magnitude of the average acceleration of the ball during this time interval?
Im not really sure...
Homework Statement
NASA operates a 2.2 second drop tower at the Glenn Research Center in Ohio, where experimental packages are dropped from the top of the tower.
a) What is the drop distance of a 2.2 s tower?
b) How fast are the experiments traveling when they hit the airbags at the bottom...
Homework Statement
The average speed of a nitrogen molecule in air is about 6.70 multiplied by 102 m/s, and its mass is about 4.68 multiplied by 10-26 kg.
(a) If it takes 1.80 multiplied by 10-13 s for a nitrogen molecule to hit a wall and rebound with the same speed but moving in an...
I haven't done anything Physics related in 2 years (high school) and am trying to get back into being familiar with Physics, Science, and mathematical terms for an upcoming class.
Homework Statement
A gazelle starts from rest and runs in a straight line 29° north of west. After 36s of...
Homework Statement
An object moves along a circular path with a constant speed, |v|.
The average acceleration in going from A to B is
1. south
2. zero
3. west
4. north
5. east
6. none of the others
Homework Equations
a = Δv / Δt
tangential acceleration = mv^2 / r...
1. An electric train initially moving at 25km/h accelerates to 35km/h in 20s. Find its average acceleration in m/s^2.
G: v1 = 25km/h
v2 = 35km/h
Delta t = 20s
R: Aav
2. Aav=(v2-v1)/delta t
3. = (35km/h-25km/h)-20s
The problem is that the velocities are in km per...
[b]1. A ball is dropeed from a height of 2.5m and rebounds to a height of 2.1m. If the ball is in contact with the floor for .70ms determine 1: direction and 2: the magnitude of the balls average acceleration due to the floor
I know the equation for average acceleration = change in...
Homework Statement
The given data is a graph depicting the distance (km) that a bus travels over 3.5 hours. The trip is broken up into three linear segments. I am supposed to find the average acceleration over the entire trip in km/hr^2. I am told that the answer will be negative.
Edit...
A 49.0-g Super Ball traveling at 27.0 m/s bounces off a brick wall and rebounds at 19.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 3.65 ms, what is the magnitude of the average acceleration of the ball during this time interval?
I converted 3.65...
Homework Statement
At t = 0, an automobile traveling north begins to make a turn. It follows one-quarter of the arc of a circle of radius 10.5 m until, at t = 1.42 s, it is traveling east. The car does not alter its speed during the turn.
Find the car's speed.
Find the change in it's velocity...
An Olympic sprinter can accelerate from rest out of the blocks to a top speed of about 11.5 m/s. This is accomplished in the first 15 m of a race. What is the average acceleration of the first sprinter?
Given- vi- 11.5 m/s
Distance-15m
Vf-?
t-?
Which formula do I use to find these...
Homework Statement
I will just try to post the whole questions, maybe my idiot eyes missed something...
an arrow is accelerated for a displacement of 75cm [fwd]
while it is on the bow, if the arrow leaves the bow at a velocity of 75m/s [fwd]
what is it's average acceleration while it's on...
Homework Statement
A car traveling in a straight line has a velocity of 5.51 m/s at some instant. After 7.36 s, its velocity is 8.09 m/s.
What is its average acceleration in this time interval?
Answer in units of m/s^2.
Homework Equations
avg. acceleration = (v2 - v1) / (t2 - t1)...
Homework Statement
The graph of displacement as a function of time of the object is shown below
[PLAIN]http://img11.imageshack.us/img11/8962/displaceemt.jpg
What is the average acceleration of the object ?
Homework Equations
The Attempt at a Solution
From the graph, I think the...
Homework Statement
Running with an initial velocity of 12 m/s, a horse has an average acceleration of -1.79 m/s^2
How long does it take for the horse to decrease its velocity to 7.0m/s ?
Homework Equations
The Attempt at a Solution
ok i got the answer is 2.8 seconds however i got there by...
Homework Statement
The acceleration of a particle moving only on a horizontal xy plane is given by a= (3t)i + (4t)j, where 'a' is in m/s*2 and t is in seconds. At t=0, the position vector r= (20m)i + (40m)j locates the particle, which then has the velocity vector v=(5m/s)i + (2m/s)j. At...
Homework Statement
A large man inhales a quantity of helium in order to fly east. If he is capable of flying at 26 km'hr by waving his arms and there is a wind of 10 km/h [S20E], find his heading and ground speed
Homework Equations
The Attempt at a Solution
Branden runs for a ball from a dead stop. It takes him 3 sec to reach it after traveling 10 meters.
What was his average acceleration?
What velocity did he achieve when he caught the ball?
Thank you!
Homework Statement
A car's velocity as a function of time is given by vx(t) = a + bt2, where a=3.00m/s and b=0.100m/s3. Calculate the average acceleration from interval t=0 to t=5.00s.
Homework Equations
Ave Acceleration = v2-v1/t2-t1
The Attempt at a Solution
After plugging in...
Homework Statement
From t = 0 to t = 5.00 min, a man stands still, and from t = 5.00 min to t = 10.0 min, he walks briskly in a straight line at a constant speed of 2.5 m/s.
What is his average acceleration aavg in the interval 2.00 min to 8.00 min?
Homework Equations
I know that in...
[b]1. A golf ball released from a height of 1.50 m above a concrete floor, bounces back to a height of 0.62 m. If the ball is in contact with the floor for 5.39 ms, what is the magnitude of the average acceleration a of the ball while it is in contact with the floor?
[b]2...
Homework Statement
the problem in a game asked me about average accelration
http://keddo.net/up/images/76ld3092n3dq9exr2rst.png
hint:
[PLAIN][PLAIN]http://keddo.net/up/images/xhb5m73r6xz5tduy6pe8.png
Homework Equations
i think it is:
a=2d/s^2
or
a=d/s^2
The Attempt at a...
Homework Statement
A tennis ball with a velocity of 7.97 m/s to the right is thrown perpendicularly at a wall. After striking the wall, the ball rebounds in the opposite direction with a velocity of −5.07 m/s to the left. If the ball is in contact with the wall for 0.011 s, what is the average...
Homework Statement
http://img30.imageshack.us/img30/3598/physicsproblem.png
The Attempt at a Solution
I don't know how to approach it with the given data set.
Homework Statement
A ball falls on the surface from 10m height and rebounds to 2.5m.If duration of contact with floor is 0.01 sec,then average acceleration during contact is-
g = 10m/s^2
Homework Equations
\alpha = \frac{v_2 + v_1}{t}
The Attempt at a Solution
Now here
v_{1}...
Homework Statement
A. A Volkswagen Rabbit has a mass of 1090 Kg and can go from 0mi/hour to 65 mi/hour in 12.0 seconds with an average acceleartion of 2.42 m/s^2. Disregarding friction, what force must the engine be producing?
B.
Disregarding friction, how much mass would need to be...
a rock is rolled in the sand and it starts at 5 meters/second, it moves in a straight line for a distance of 3 meters and then stops...what is the magnitude of the average acceleration.??
my attempt at this was to simply divide 5 by 3 giving me 1.6 m/s
is this correct ?
A bird is flying north at 5 m/s. The bird veers and travels at 5 m/s east. This happens over a 2 second period. what is the average acceleration (magnitude and direction) during this 2 second interval?
Homework Statement
a car traveling at a constant speed of 20 m/s that is initially traveling due northwast rounds a corner so that after 10s, the car is traveling due northeast. What are the magnitude and direction of the car's average acceleration during this interval of time?
Homework...
Homework Statement
Earth's orbit around the SUn is nearly circular. THe period is 1 year = 365.25 days. In an elapsed time of 2.70 days, what is Earth's angular displacement? what is the change in Earth's velocity (perpendicular to the average velocity) What is the Earth's average acceleration...
I have a few question regarding Acceleration, I am not sure exactly how to get average acceleration from a acceleration vs. time graph. Do you make a slope? I drew a sample graph, say get the average acceleration from 11s - 25s? Would you try to draw a slope between the two time intervals...
Homework Statement
A golf ball released from a height of 1.5m above a concrete floor bounces back to a height of 1.1m. If the ball is in contact with the floor for 6.2 X 10^-4 s, what is the average acceleration of the ball while in contact with the floor?
g= 9.81 m/s^2
x-xo= -1.5
vo= 0...
Initially, a particle is moving at 5.27 m/s at an angle of 35.9° above the horizontal. Two seconds later, its velocity is 6.27 m/s at an angle of 57.4° below the horizontal. What was the particle's average acceleration during these 2.00 seconds in the x-direction and the y-direction...
Homework Statement
A car initially moving at 12 m/s [E 30o N] accelerates until it reaches a final velocity of 10 m/s [E]. What was the average acceleration of the car?
I couldn't attempt anything. There isn't any magnitude given save for velocity, so I have no clue how to solve this, and...
A sports car accelerates from rest to 98 km/hr in 18 s. What is its average acceleration in m/s^2?NOTE: Do NOT include units in your answer, just type in the number value!
What I did was immediately make 98 km into 98000 meters. I then took 98000 and divided it by 60 twice (once would make it...
[b]1. At t = 0, an automobile traveling north begins to make a turn. It follows one-quarter of the arc of a circle of radius 9.3 m until, at t = 1.60 s, it is traveling east. The car does not alter its speed during the turn.
(a) Find the car's speed.
(b) Find the change in its velocity...
[b]1. At t = 0, an automobile traveling north begins to make a turn. It follows one-quarter of the arc of a circle of radius 9.3 m until, at t = 1.60 s, it is traveling east. The car does not alter its speed during the turn.
(a) Find the car's speed.
(b) Find the change in its velocity...
A 50.0 g Super Ball traveling at 25.0 m/s bounces off a brick wall and rebounds at 21.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 5.00 ms, what is the magnitude of the average acceleration of the ball during this time interval? (Note: 1 ms = 10-3...
Homework Statement
Calculate the speed of the minute hand on the clock (I solved with the assumption of the minute hand being the radius) with the length of 25 cm.
How many degrees did the minute hand move through from 12" point to 2" point?
What is the average acceleration...
Homework Statement
An object moving with a constant acceleration travels 13 m in 7.8 s. The acceleration is then changed and the object covers an additional 34 m in 1.7 s. What is the average acceleration of the object over the entire interval described?
Homework Equations
Xf1 = 1/2(vo +vf)t...
can i take calc. the average acceleration (m/s2) of 3 objects by adding them and dividing the answer by 3 if the measuretime is more or less equal for the 3 objects? or what should i do different?
do you not have to take into account that you are adding and dividing logarithms? and can you do...
Homework Statement
I'ts part of a bigger problem, but this is all the info given.
http://img238.imageshack.us/img238/7923/chartro3.jpg
Homework Equations
I'm doing an experimental error calculation, and that equation wouldn't relevant, but that's the only one I got.
The Attempt...
Homework Statement
A car traveling at a constant speed of 20 m/s that is initially traveling due northwest rounds a corner so that after 10 s, the car is traveling due northeast. What are the magnitude and direction of the car's average acceleration during this interval of time? Be sure to...
Homework Statement
A rock is rolled in the sand. It starts at 5.0 m/s, moves in a straight line for a distance of 3.0m and then stops. What is the magnitude of the average acceleration?
Homework Equations
aavg = change in V/ change in time
magnitude of acceleration = change of speed/time...