Constant acceleration Definition and 340 Threads

Homework Statement A truck travels at a constant speed of 28.0 m/s in the fast lane of a two-lane highway. It approaches a stationary car stopped a the side of the road. When the truck is still 125 m behind the car, the car pulls out into the slow lane with an acceleration of 2.6 m/s2. How...

Homework Statement A rabbit runs past a bush where a wolf is lying in wait. The rabbit is running at 3.0 m/s. The wolf leaps out 0.50 seconds after the rabbit has passed and accelerates at 1.2 m/s2 chasing after the rabbit. If the wolf can keep up this acceleration, how long will it take for...

A basketball player grabbing a rebound jumps 76.1 cm vertically. How much total time (ascent and descent) does the player spend (a) in the top 14.4 cm of this jump and (b) in the bottom 14.4 cm? Do your results explain why such players seem to hang in the air at the top of a jump? so the only...

Homework Statement A train pulls away from a station with a constant acceleration of 0.40 m/s^2. A passenger arrives at a point next to the track 6.0 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...

Homework Statement At the instant the traffic light turns green, a car that has been waiting at an intersection starts ahead with a constant acceleration of 3.60 m/s^2. At the same instant a truck, traveling with a constant speed of 20.5 m/s, overtakes and passes the car. How far beyond its...

In coming to a stop, a car leaves skid marks 92 m long on the highway. Assuming a constant deceleration of 7.00 m/s^2, estimate the speed of the car just before breaking. I think my knowns are the initial position (0 m), final position (92m), acceleration (7.00 m/s^2) and final velocity (0...

Hi, I'm trying to solve something that I'm very sure is simple, I just can't seem to find the right equation. A rocket is traveling straight up, with an acceleration of 20m/s^2. I need to know how long it takes to reach a height of 1379.8m (this is the second part of a question). I am...

Is it possible to make an object travel with a constant acceleration using sustained nuclear chain reaction in space?

My book has stumped me on something that I thought should be simple... perhaps I'm just not getting it. Section - Constant Acceleration It states the following: "When acceleration is constant, the average acceleration and instantaneous acceleration are equal and we can write... a =...

I have a question regarding the formula d=Vave*t can this formula be used when you have constant acceleration ?

Homework Statement A particle moving at 5 m/s reverses its direction in 1s to move at 5 m/s in the opposite direction. If is acceleration is constant, what distance does it travel? Homework Equations The constant acceleration equations The Attempt at a Solution I use x=vot +...

Homework Statement In coming to a stop, a car leaves skid marks 92m long on the highway. Assuming a deceleration of 7.00m/s^2 estimate the speed of the car just before braking. Homework Equations deceleration=7m/s^2, distance=92m The Attempt at a Solution I found there was not...

Can some one please prove that Vav=(Vi+Vf)/2 is valid only for constant acceleration?

Homework Statement Find the time it takes to traverse the distance. Given: *constant velocity *initial acceleration = 0 *ending acceleration= 11176 m/s *distance traversed = 28.96 km (18 miles) Homework Equations velocity: v^2 = v0^2 + 2a(delta x) v = sqrt(v0^2 + 2a(delta x))...

Homework Statement "The 100- dash can be run by the best sprinters in 10.0 . A 64- sprinter accelerates uniformly for the first 41 to reach top speed, which he maintains for the remaining 59 ." What is the average horizontal component of force exerted on his feet by the ground during...

Homework Statement Two cars drive on a straight highway. At time t = 0, car 1 passes mile marker 0 traveling due east with a speed of 18.0 m/s. At the same time, car 2 is 0.90 km east of mile marker 0 traveling at 30.0 m/s due west. Car 1 is speeding up with an acceleration of magnitude 0.40...

Homework Statement A particle moving along a straight line with constant acceleration starts its motion at t = 0. The particle is observed to change direction at t=4s, and when t=10s it reaches the position of -2 m with a velocity of -2.4 m/s measured from a chosen reference frame. Find the...

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 a time of 1.14 s later. You may ignore air resistance. A.) If the height of the building is 20.6 m, what must the initial speed be of the first ball if both are...

Homework Statement A car slows down uniformly from a speed of 21.0 m/s to rest in 6.00s. How far did it travel in that time? Homework Equations I am not really sure what one to use, which is the problem. The Attempt at a Solution

Homework Statement A light plane must reach a speed of 33 m/s for takeoff. How long a runway is needed if the (constant) acceleration is 3.0m/s^2? Homework Equations I looked at the Kinematics Equations and tried to re-arrange them to be able to find the distance with what I was given...

Homework Statement A car accelerates from 13 m/s to 25 m/s in 6.0s. What was its acceleration? How far did it travel in this time? Assume constant acceleration. Homework Equations I used the equation a=v/t The Attempt at a Solution I got that the acceleration is 2.0 m/s^2. Now my...

Homework Statement an antelope moving with constant acceleration covers the distance between two points 70.0 m apart in 7.0 s. Its speed as it passes the second point in 15.0 m/s . a) what is its speed at the first point? b)what is the acceleration? Homework Equations what do you...

1. A tennis ball on Mars, where the acceleration due to gravity is .379g and air resistance is negligible, is hit directly upward and returns to the same level 8.5 s later. (a) How high above its original point did the ball go? (b) How fast was it moving just after being hit? 2. v (y)=...

1. Homework Statement A jumbo jet needs to reach a speed of 300 km/hr on a runway for take off. Assuming a constant acceleration and a runway 2 km long, what minimum acceleration from rest is required to get the jet in the air? 2. Homework Equations I tried using the equation...

Hello everyone, Normally if there is 1 kg object and I apply 10 N force it would accelerate at 10m/s. Here the acceleration is determined by the mass of object. How does gravity in the absense of resistance make objects travel at a fixed acceleration? In a centrifuge a force equivalent to...

Homework Statement A wheel rotates with a constant angular acceleration of 3.71 rad/s2. what angle does the wheel rotate between t = 2.00 s and t = 6.25 s? Homework Equations \omega=\omega_{i}+\frac{1}{2}\alpha t^{2} Δθ = θf - θi = ωit + αt2 The Attempt at a Solution I found...

1. Homework Statement A package is dropped from a helicopter. Note that both the helicopter and package are traveling upward at 10.0m/s when the package is released. If the package takes 3.5 seconds to hit the ground, how high was the helicopter when the package was released? If the...

1. The problem A motorcyclist slows down uniformly as he approaches a red light. He takes 3.2 seconds to come to a halt and travels 40m in this time. How fast was he traveling initially? Homework Equations s=(u+v)/2*t

Homework Statement The world record for the 100m dash is 9.58s, and for the 60m dash it is 6.38s. Assume a sprinter accelerates at a constant rate up to a maximum velocity that is maintained for the rest of the race, no matter how long it is. a) Find the acceleration (both sprinters will...

Homework Statement A speedboat starts from rest and accelerates at +2.01 m/s2 for 6.55 s. At the end of this time, the boat continues for an additional 6.45 s with an acceleration of +0.518 m/s2. Following this, the boat accelerates at -1.49 m/s2 for 8.80 s. Find the total displacement of...

Homework Statement To demonstrate the tremendous acceleration of a top fuel drag racer, you attempt to run your car into the back of a dragster that is "burning out" at the red light before the start of a race. (Burning out means spinning the tires at high speed to heat the tread and make the...

Greetings, Here is my following question 1. During volcanic eruptions, chunks of solid rock can be blasted out of the volcano; these projectiles are called volcanic bombs. Figure 4-58 shows a cross section of Mt. Fuji, in Japan. (a) At what initial speed would a bomb have to be ejected, at...

Homework Statement A rocket starting at rest takes on a net acceleration of 20m/s^2 in a vertical line until it runs out of fuel after 5 seconds. At what height does it run out of fuel? What is its velocity when it runs out of fuel? What is its maximum height? How long does it take to hit the...

Homework Statement A falling object travels one-fourth of its total distance in the last second of its fall. From what height was it dropped? Homework Equations equations of motion for constant acceleration Thanks in advance !

Homework Statement I have a conceptual problem that involves logger pro. Unfortunately, I do not have access to logger pro. Here it is: Suppose you have used a motion detector to collect data for an object that is moving with constant acceleration. Describe how to use LoggerPro to...

Homework Statement Speedy Sue, driving at 33.0 m/s, enters a one-lane tunnel. She then observes a slow-moving van 165 m ahead traveling with velocity 5.20 m/s. Sue applies her brakes but can accelerate only at -2.00 m/s2 because the road is wet. Will there be a collision? If yes, determine...

A truck covers 40.0 m in 8.50 s while smoothly slowing down to a final velocity of 2.80 m/s a. Find the truck's original speed. b. Find its acceleration a) I'm using x=1/2(vo+v)t to find the original velocity but I keep getting vo=12.21m/s (the books answer is 6.61m/s) b) For the...

Homework Statement An automobile speeding at 28.33 m/s passes a stationary police cruiser. The police officer starts to move her cruiser in persuit 11.00s after the automobile passes. She accelerated uniformly to 34.72 m/s in 11s and then continues at uniform speed until she catches the...

Homework Statement (1) If you measure the acceleration of the falling mass to be 7.2 m/s^2, should you be concerned that you somehow made a mistake? What if you found the acceleration to be 11.5 m/s^2? For this question, a falling mass is attached to a piece of paper, which is subsequently...

Homework Statement A cyclist is traveling along a straight horizontal road. as she passes a bus stop she sees a red traffic light ahead of her. She continues to travel with a constand speed of 3 ms^-1 for 20 seconds and then decelerates at a constant rate of 0.2ns^-2 until coming to rest at...

Homework Statement A hockey puck sliding on a frozen lake comes to rest after traveling 249 m. If its initial velocity is 4.5 m/s, what is its acceleration if that acceleration is assumed constant? Homework Equations V(t)= v(initial) + at d= v(initial)*t + .5at^2 The Attempt at a...

I'm having trouble with this problem mostly because I can't think of the logic behind it, so I don't know which of the basic formulae to use. Excuse my "noobieness" as I'm a first-year physics student. The question states, "Two trains face each other on adjacent tracks. They are initially at...

Homework Statement A cheetah is hunting. Its prey runs for 3.2 s at a constant velocity of +10.0 m/s. Starting from rest, what constant acceleration must the cheetah maintain in order to run the same distance as its prey runs in the same time? Homework Equations V=Vo + a(t) The...

If I have a rocket constantly accelerating at some rate a, (requiring some constant force F), I want to know how much work is done by the rocket to travel a given proper length. For example, a rocket traveling to alpha centauri at 1g acceleration half way and 1g acceleration the other half...

Homework Statement Hi, I am working on a camera system in flash, and am trying to implement an ease in/out effect where the camera moves between two points, with positive acceleration up to the midpoint, and then negative accelaration up to the end point. I've had a look through the equations...

Homework Statement a red car and a green car, identical except for the color, move toward each other in adjacent lanes and parallel to an x axis. At time t = 0, the red car is at xr = 0 and the green car is at xg = 250 m. If the red car has a constant velocity of 23.0 km/h, the cars pass each...

Homework Statement A hot air balloon ascending at a rate of 10m/s drops a package when the balloon reaches a height of 73 m. Find time to ground. Find velocity when package hits ground. The balloon and package, in this case, can be treated as a point particles and as such can be...

Hi everyone, According to the equation Power = Force x Velocity or P = mav or a= P/mv, in order to keep say a rocket at constant accelration would require a CONSTANT INCREASE IN ENERGY INPUT PER UNIT TIME. This is somehow problematic to visualize for me. It would mean that accelerating a rocket...

Homework Statement Liz rushes down onto a subway platform to find her train already departing. She stops and watches the cars go by. Each car is 8.60 m long. The first moves past her in 1.50 s and the second in 1.10 s. Find the constant acceleration of the train. Homework Equations...

I'm having trouble finding the equation. Two cars are traveling along a straight road. Car A maintains a constant speed of 80 km/h and car B maintains a constant speed of 110 km/h. At t=0, car B is 45 km behind car A. (A) How much father will car A travel before car B overtakes it? (B) How...