Concept explainers
A glider of length ℓ moves through a stationary photogate on an air track. A photogate (Fig. P2.19) is a device that measures the time interval Δtd during which the glider blocks a beam of infrared light passing across the photogate. The ratio vd = ℓ/Δtd is the average velocity of the glider over this part of its motion. Suppose the glider moves with constant acceleration. (a) Argue for or against the idea that vd is equal to the instantaneous velocity of the glider when it is halfway through the photogate in space. (b) Argue for or against the idea that vd is equal to the instantaneous velocity of the glider when it is halfway through the photogate in time.
Figure P2.19
Trending nowThis is a popular solution!
Chapter 2 Solutions
Physics for Scientists and Engineers, Technology Update (No access codes included)
Additional Science Textbook Solutions
Physics: Principles with Applications
Lecture- Tutorials for Introductory Astronomy
Essential Cosmic Perspective
The Cosmic Perspective Fundamentals (2nd Edition)
Loose Leaf For Explorations: Introduction To Astronomy
The Physics of Everyday Phenomena
- A thief is trying to escape from a parking garage after completing a robbery, and the thief’s car is speeding (v = 12 m/s) toward the door of the parking garage (Fig. P2.60). When the thief is L = 30 m from the door, a police officer flips a switch to close the garage door. The door starts at a height of 2.0 m and moves downward at 0.20 m/s. If the thief’s car is 1.4 m tall, will the thief escape?arrow_forwardA thief is trying to escape from a parking garage after completing a robbery, and the thief's car is speeding (v = 12 m/s) toward the door of the parking garage (Fig. P2.60). When the thief is L= 30 m from the door, a police officer flips a switch to close the garage door. The door starts at a height of 2.0 m and moves downward at 0.20 m/s. If the thief's car is 1.4 m tall, will the thief escape? Garage door L Figure P2.60arrow_forwardA 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 measurement of this cat's motion and construct a graph of the feline's velocity as a function of time. What distance (in cm) does the cat move from t=0 to t=7.5s?arrow_forward
- A common graphical representation of motion along a straight line is the v vs. t graph, that is, the graph of (instantaneous) velocity as a function of time. In this graph, time t is plotted on the horizontal axis and velocity v on the vertical axis. Note that by definition, velocity and acceleration are vector quantities. In straight-line motion, however, these vectors have only a single nonzero component in the direction of motion. Thus, in this problem, we will call the velocity and a the acceleration, even though they are really the components of the velocity and acceleration vectors in the direction of motion, respectively. Figure U₁(m/s) 2.0 1.5 1.0 0.5 1(s) 0 10 20 30 40 50 1 of 1 (Figure 1) is a plot of velocity versus time for a particle that travels along a straight line with a varying velocity. Refer to this plot to answer the following questions. Part A What is the initial velocity of the particle, vo? Express your answer in meters per second. ▸ View Available Hint(s) V₁ =…arrow_forwardIn the children's book Nuts to You, a young squirrel named Jed is snatched up by a hawk. While in the air Jed manages to go limp, slip through the hawk's talons and fall to the forest floor. The hawk travels horizontally at a speed of 4.86m/s . (You may neglect any effects of air resistance as you answer the following questions). One second after being released, what is the y-component of Jed's velocity?arrow_forwardThe velocity of a particle is given by v = 23t2 - 110t + 52, where v is in meters per second and t is in seconds. Plot the velocity v and acceleration a versus time for the first 6.4 seconds of motion and evaluate the velocity when a is zero. Make the plots and then answer the questions. Questions: When t = 0.8 s, V = i m/s, a = i m/s2 When t = 3.7 s, V = i m/s, a = i m/s? When t = 4.7 s, V = i m/s, a = i m/s? When a = 0, V = m/sarrow_forward
- How do I solve part b?arrow_forwardConsider a particle moving along the x-axis with acceleration a(t) = 2t and an initial velocity, v(0) = -2. a. Find the displacement of the particle from t = 0 to t = 4. (2 points) The displacement of the particle is units. Round your answer to the nearest thousandth if necessary. b. Find the total distance traveled by the particle from t = 0 to t = 4. The total distance traveled by the particle is units. Round your answer to the nearest thousandth if necessary.arrow_forwardSome troublemaking kids are dropping water balloons from the roof of your apartment building. You are in your fifth-floor room and your window is 25 m above the sidewalk outside. You look outside and see that each balloon hits the pavement 1.5 s after passing your window. Express answers using 2 significant figures. a) How fast are the balloons traveling when they pass your window? b) Assuming the balloons are being released from rest, from what height above your window are they being released? c) If you threw a balloon upwards from your window with an initial speed of 6.5 m/s, would you be able to get it to the roof?arrow_forward
- Starting from rest, a particle moving in a straight line has an acceleration of a = (2t−6)m/s^2 , where t is in seconds. What is the particle’s velocity when t = 6s, and what is its position when t = 11s? Create a plot for position, velocity, and acceleration versus time, from 0-15s. (Use integration.)arrow_forwardHello. I am working on a problem with motion. The questions asks me to calculate the maximum height (h1), total time (t2), and speed of a ball right before it hits the ground. The question states that A person is throwing a ball upward into the air with an initial speed Vo = 10m/s. Assume that the instant when the ball is released, the person's hand is at a height ho = 1.5m. The speed of the ball at its peak height is zero, and the question needs to be solved in ascending part and descending part. I don't understand how to solve for the maximum height. What is the correct formula to use and why? For other questions like this, I will be able to solve them if I know the formulas for the ascending of the ball and the descent of the ball as well as the explanation. Thank you. For the sake of the question, the ball is being thrown straight up.arrow_forwardWe are standing on the top of a 1040 feet tall building and launch a small object upward. The object's height, measured in feet, after t seconds is h(t) = 16t? + 128t + 1040. A) What is the object initial velocity? ft/second B) What is the highest point that the object reaches? feetarrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning