Constant acceleration Definition and 337 Threads

1. Question to problem A car moving with constant acceleration covered the distance between two points 57.9 m apart in 5.02 s. Its speed as it passes the second point was 14.4 m/s. (a) What was the speed at the first point? (b) What was the acceleration? (c) At what prior distance from the first...

Homework Statement At t = 0, an elevator departs from the ground with uniform speed. At time ##T_1## a child drops a marble through the floor.The marble falls with uniform acceleration g = 9.8 m/s^2, and hits the ground at time ##t = T_2##. Find the height of the elevator time ##T_1##...

Homework Statement A motorcycle has a constant acceleration of 2.80 m/s2. Both the velocity and acceleration of the motorcycle point in the same direction. How much time is required for the motorcycle to change its speed from (a)40.9 to 50.9 m/s, and (b)70.9 to 80.9 m/s? [/B]Homework Equations...

x = x0 + v0 * t + 1/2 * constant acceleration * t^2 So this is supposed to be very very simple physics, but I still feel like there's a part of this equation I don't fully understand. The first term is the initial position of the body at t=0. The second term is the initial velocity at t=0...

Homework Statement A car traveling at an unspecified constant speed passes a parked motorcycle cop. The motorcycle accelerated at an unspecified constant acceleration and reaches the car at unspecified distance d. At what point did the motorcycle's speed match that of the car, expressed as a...

A disclaimer: I'm trying to limit myself to asking questions on Physics Forums, partly because I feel I've gone way past my quota. Still, there is one question that simply won't go away, and it concerns the relative efficiencies between two forms of motion. The first involves continuous...

Homework Statement Im working with a UROV and I have a technical scenario that I am supposed to solve. It seems pretty easy but i keep getting ridiculous answers. Assuming a max thrust of 5 N for 1 motor/propeller, for the forward direction only, use the above information to determine the Max...

I'm starting to question my sanity. This wikipedia article claims a ship with a constant acceleration of 1g will cross 100000 light-years in 24 years by traveller's clock: https://en.wikipedia.org/wiki/Space_travel_using_constant_acceleration Numerous calculators over the web give you the same...

Homework Statement Two cyclists, Anant and Beth, are standing on a straight road a distance d=22.0 m apart. Simultaneously, they begin to move toward each other, Anant with acceleration a_A=0.2 m/s^2 and Beth with acceleration a_b=0.10 m/s^2. Just as they begin to move, a bee, sitting on...

Homework Statement Which one of these motions is at constant acceleration? A) A car moving at a constant speed and constant direction. B) A train making stops along its route. C) A moon orbiting a planet. Homework EquationsThe Attempt at a Solution I believe that A is an acceptable answer...

Homework Statement Two cars travel towards one another on a 21.0m road, the car traveling to the left has an acceleration a_L=2.4m/s^2 the other car an a_R=1.8m/s^2. What is the distance traveled by the left car up to the meeting point? Homework Equations Left Car...

Homework Statement "A jet plane is cruising at 300 m/s when suddenly the pilot turns the engines up to full throttle. After traveling 4.0 km, the jet is moving with a speed of 400 m/s." Homework Equations "What is the jet's acceleration, assuming it to be a constant acceleration?" The Attempt...

Homework Statement [/B] 1. Rob throws a baseball upwards at 14.2 m/s. His friend, John, is sitting in a tree 4.5m above Rob. a. Calculate how long it will take to reach John. b. If John misses the ball as it moves upwards, how long will it take to reach John again. Homework Equations...

In a car moving at constant acceleration, you travel 250 m between the instants at which the speedometer reads 40 km/h and 80 km/h. How many seconds does it take you to travel the 250 m? What is your acceleration? I have thought of finding the average of 40 km/h and 80 km/h to start the problem...

Homework Statement A person is standing over a well and drops a rock. After 2.4 seconds he hears a rock splashing into the water. Take the speed of sound to be 300m/s and calculate the depth of the well. Homework Equations x=v/t for constant velocity x=1/2at^2 for accelerated motion The...

Hello,Lets say I start off with constant acceleration of 1 m/s^2, and I want to evaluate it at 3 seconds. a = 1. a(3) = 1 then, since at=v, v(t) = at = 1(3) = 3m/s then I can work backward v/t = a = 3/3 = 1 then, since vt = d d(t) = vt = 3(3) = 9 then I can work backward d/t= v =...

Homework Statement A rock is released from rest from the top of a very high cliff, and accelerates downward at g. Approximately how far does the rock travel in the first 7 seconds of its free-fall? (Assume no air friction.) Homework Equations X=Xo+VoT+1/2AT^2 The Attempt at a Solution I...

The way I see it, a constant supply of power, say from the engine in a car to its wheels, will cause it to accelerate at a decreasing rate because the kinetic energy the power supplies is proportional to the velocity squared. That makes sense because going faster will cause the car to encounter...

Homework Statement A speeding car has instantenous velocity of 1 m/s when a stopwatch reads 10 seconds. It has constant acceleration of 2 m/s^2. What is the cars speed when it reaches the stopwatch reads 12 seconds. Homework Equations x= (Vinitial)(DeltaT) + 1/2(a09deltaT)^2 I think this is...

Homework Statement An Indy 500 race car's velocity increases from 4m/s to 36m/s over a 4 second time interval. What is its acceleration? 4m/s is the initial velocity, 36 m/s is the final velocity, and time is 4 seconds. Homework Equations final velocity = initial velocity + (acceleration x...

Homework Statement Please see attached for diagram. We know that the elevator arm is horizontal when the lift is stationary, with ## M_{1}=\frac{4M_{2}M_{3}}{(M_{2}+M_{3})}## It wants us to find out if this is still the case when the lift is accelerated upwards at a constant velocity ##g##...

What does the metric look like for constant uniform acceleration, say in the x-direction? ds^2 = g_tt (cdt)^2 + g_xx (dx)^2 g_tt = ? g_xx = ?

It's a combination of centrifugal force and gravity that allows constant acceleration of a rotating object? also is it just coincidence that the most dense objects are near the sun?

Hello! Well, I am in trouble with this question for some time. I am making a simulator with autonomous cars and its movement is done applying constant impulses to the wheel. My question is: if the vehicle is in the intertia state and I start to apply this impulses, the vehicle will assume a...

Homework Statement During a tennis serve, the ball goes from rest to approximately 32.3 m/s. The average power generated during the serve is equal to 2672 Watts. If the acceleration is constant during the serve, what is the magnitude of the force acting on the ball? Homework Equations P= F v...

< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown >[/color] Hello, I'v been trying to find an answer for this question for quite some time, I always hit a complex trigonometric equation or a 4th degree polynomial equation. any help would be very...

1. A 92 kg water skier floating in a lake is pulled from rest to a speed of 12 meters/second in a distance of 25 meters. What is the net force exerted on the skier, with the assumption that his acceleration is constant?2. Force = Mass x Acceleration3. As far as I know, from using the equation...

In cases like projectile motion, although the acceleration vector is constant (ignoring air resistance), a single coordinate axis fails to describe the motion of the particle, since it occurs in a plane; therefore we need a minimum of two coordinate axes to fully describe the trajectory of that...

1. A cat walks in a straight line, which we shall call the x-axis with the positive direction to the right. As an observant physicist, you make measurements of this cat's motion and construct a graph of the feline's velocity as a function of time the figure...

Hello, this is my first post on PhysicsForums. I'm a first year student at the University of Kansas pursuing a Bachelor of Science in Physics and Astronomy (double majoring). The wording on my homework (for Honors General Physics 1) is a little bit strange to me so maybe some of you guys and...

An object has initial speed u and acceleration a. After traveling a distance s, its final speed is v. Which of the following includes the two conditions necessary for the equation, v^2 = u^2 +2as, to apply? I know the answer is a has constant magnitude and a has constant direction, but I am...

Hello, I am currently by some reason struggling with this problem. I cannot seem to get the correct reasoning here. I would appreciate any help! 1. Homework Statement Ann and Lisa cross the 100 m finish line at the same time, 10.2 s after start. Both had constant acceleration until they...

Homework Statement [/B] At t=0, a flywheel has an angular velocity of 3.4 rad/s, an angular acceleration of -0.42 rad/s^2 and a reference line at \theta_0 =0 A: Throigh what maximum angle will the reference line turn in the positive direction B: At what times will the reference line be at...

Homework Statement A train pulls away from a station with a constant acceleration of 0.4 m/s2. A passenger arrives at a point next to the track 6 s after the end of the train has passed the very same point. What is the slowest constant speed at which she can run and still catch the train...

The problem statement A train starts out from Stavanger at 8.14, in direction of Kristiansand. It goes with constant speed, 80.0km/h until Sandnes, a distance of 15.0 km. Then it accelerates (instantaneously) to 120 km/h and proceeds towards Kristiansand. Kristiansand is 250 km from...

Homework Statement Starting from rest, a particle moves along an x-axis from point A to point B with constant acceleration a1 = 2.20 m/s2 through displacement d1 = 500 m. Then it slows at constant acceleration a2 through displacement d2 = 300 m from point B to point C where it is again at...

[SIZE="4"]Definition/Summary Three simple equations of motion may be used when acceleration is constant in both magnitude and direction, or when acceleration is constant in magnitude and the motion is forced to follow a fixed track. These three equations apply only in the direction of the...

Homework Statement Can an object with constant acceleration reverse its direction of travel? Can it reverse its direction twice? Homework Equations Basic kinematics. The Attempt at a Solution First I thought that it is not possible to reverse direction because if direction...

This is a very basic question. We know for a particle moving under constant acceleration we can use both the equations x = \frac{v + v_0}{2}t and x = v_0t + \frac{1}{2}at^2 If we want to find t form each of these equations, the first one gives only one value but the second one gives two...

A rock is thrown vertically upward from ground level at time t = 0. At t = 1.6 s it passes the top of a tall tower, and 2.0 s later it reaches its maximum height. What is the height of the tower? My thought process: First find initial velocity: v=vo+at 0=vo+(-9.8)(2) vo=19.6 m/s...

Homework Statement A jet plane is cruising at 300 m/s when suddenly the pilot turns the engine up to full throttle. After traveling 4km, the jet is moving 400 m/s. What is the jet's acceleration? known: x0 = 0m, t0 = 0s, v0 = 300 m/s x1 = 4000m, t1 = ?, v1 = 400 m/s Homework...

Greetings, I'm having some issues with a problem that I is related, though not identical, to Bell's spaceship paradox (this is not for a homework or anything, it just sort of occurred to me when I was thinking about something else). Consider two particles that are initially at rest in some...

An antelope moving with constant acceleration covers the distance 80.0m between two points in time 6.70s. Its speed as it passes the second point is 14.6 m/s. 1) What is its speed at the first point? 2) What is the acceleration? First I understand that when we have (constant acceleration)...

This isn't actually a homework question, it's for a vehicle safety project at work, but I think it fits in this forum. Homework Statement A truck is traveling down the road at 60 mph, and begins to decelerate at a rate of 0.8 g. I'd like to find the total distance it takes the truck to...

I'm new to physics, so I'm sure the explanation is very simple, but I cannot wrap my head around Newton's 2nd law F=ma. It is very easy to understand until I plug 0 into a. Wouldn't this make the force of the reaction disappear? For instance if a 100kg rock traveling east at constant velocity...

I appologize for any spelling or grammar errors. Please take into account that English isn't my first language and that I haven't finished my English course yet, since I'm 14 years old. My Question (which I suppose is very dumb): Imagine there is a manned spacecraft traveling through deep...

Homework Statement At the instant the traffic light turns green, a car starts with a constant acceleration of 5.00 ft/s^2. At the same instant a truck, traveling with a constant speed of 70.0 ft/s, overtakes and passes the car. How far from the starting point (in feet) will the car overtake...

Homework Statement A motorist suddenly notices a stalled car and slams on the brakes, negatively accelerating at 6.1m/s2 . Unfortunately this isn't enough, and a collision ensues. From the damage sustained, police estimate that the car was going 22km/h at the time of the collision. They also...

Homework Statement I want to cover a distance of 8,ooo,ooo,ooo,ooo m and I want to know the time it will take if I have an initial velocity of 176400 m/ sec with an acceleration of 19.6 m/sec2. I think I have the right equation here I'm just not sure how to solve for t. Could someone walk me...

I'm making research for an article about constant acceleration / deceleration ship propulsion. Now, it's about 30 years since I was solving differential equations so there's no way I could solve, let alone devise, an appropriate differential equation. I'm not even sure an appropriate...