Section 3: Falling Objects

Slides:



Advertisements
Similar presentations
Freefall Motion Notes Any object near the surface of the Earth experiences the pull of gravity. If released from rest, the object will fall freely toward.
Advertisements

Free Fall Projectile Motion – free fall, but not vertical.
Free Fall Chapter 2 Section 3. Free Fall  Free Fall – An object in free fall falls at a constant acceleration towards the surface of a planet neglecting.
Today’s Topic Free Fall What is Free Fall? Free Fall is when an object moves downward (vertically) only as the result of gravity.
Free Fall Chapter 2 Section 3.
Falling Balls 1 Falling Balls. Falling Balls 2 Introductory Question Suppose I throw a ball upward into the air. After the ball leaves my hand, is there.
Physics Motion. Mechanics is the study of motion, and the forces and energies that affect motion. -Kinematics describes how objects move -Dynamics describes.
Free Fall. Up and Down  Two balls are thrown at the same initial speed, one upward and one downward with negligible air resistance. When the balls strike.
Motion in One Dimension Free Falling Objects
You are going 25 m/s North on I-35. You see a cop parked on the side of the road. What is his velocity related to you. A.25 m/s South B.25 m/s North C.0.
Physics 521 Section 2.4 and Chapter 3.  Acceleration is the rate at which the velocity of an object changes.  When the velocity changes ( ) during some.
Free Fall Free fall: when an object is only affected by gravity
DISPLACEMENT AND VELOCITY Chapter 2-1. Objectives Describe motion in terms of frame of reference, displacement, time and velocity. Calculate displacement,
Acceleration Due to Gravity EQ: How is the motion of an object moving vertically different from one moving horizontally? EQ: How is the motion of an object.
Free Fall Motion Notes Day 4.
 What is the unit we use for speed?  m/s  What is the term for speed and direction?
Acceleration due to Gravity. Gravity is… acceleration of an object toward the center of the Earth The acceleration of an object toward the center of the.
Notes on Motion VI Free Fall A Special type of uniform acceleration.
Chapter 4Linear motion. 1) You can describe the motion of an object by its position, speed, direction and acceleration.
Notes on Motion VI Free Fall A Special type of uniform acceleration.
Gravity and Acceleration Objects near the surface of Earth fall to Earth due to the force of gravity.  Gravity is a pulling force that acts between two.
Chapter 3 Kinematics in Two Dimensions. 3.1 – d, v, & a A bullet is fired horizontally. A second bullet is dropped at the same time and at from the same.
2-3 Falling Objects  Gravity - the force of attraction between all matter.  Gravity – one of the FOUR FUNDAMENTAL FORCES in nature.  If there is NO.
1.A water skier is pulled by a boat with an initial velocity of 10 m/s, The boat then accelerates to a velocity of 15 m/s over the next 12.5 s. What is.
Learning Target 5 → Free Fall: I can use the acceleration of gravity to describe and calculate an object's motion 5.1 I can describe how and why the rate.
Chapter 3 Accelerated Motion. Introduction In this chapter we will examine acceleration and define it in terms of velocity. We will also solve problems.
 Vertical projectile motion deals with objects that fall straight down, objects that get thrown straight up and the motion of an object as it goes straight.
If your pen falls off your desk does it accelerate? If I drop a pen, what is its initial speed? How fast is it going just before it hits the ground? ZERO.
9.2 – Calculating Acceleration The acceleration of an object depends on the change in velocity and the time required to change the velocity. When stopping.
VERTICAL ONE DIMENSIONAL MOTION.  Relate the motion of a freely falling body to motion with constant acceleration.  Calculate displacement, velocity,
Chapter 2: Section 3 Source:
Forces in Motion Chapter 2 Mrs. Estevez. Gravity and Motion What happens when you drop a baseball and a marble at the same time? What happens when you.
Gravity and Motion Chapter 2 Section 1
1 Physics Chapter 2 Motion in One Dimension Topics:Displacement & Velocity Acceleration Falling Objects.
An object that the only force acting on it is gravity Mr. P.
 How is free fall acceleration different from regular acceleration you experience in your car?  Name three ways physics is used in your home.
Free Fall Think about an apple falling from a tree. – It starts at rest and gains speed as it falls, or accelerates. Gravity causes the apple to accelerate.
Motion in One Dimension Free Falling Objects
a = g = m/s/s a = g = -10 m/s2 2-3 Falling Objects
3.3 Uniform Acceleration and Free Fall
Calculate the car’s average VELOCITY
Gravity and Acceleration
Chapter 3 Section Projectile Motion.
Section 3 Falling Objects
Acceleration.
Freefall & Vertical Motion
Free Fall Free Fall Examples
Free Fall All bodies accelerate downwards at -10m/s2 on earth regardless of mass (in the absence of air resistance). On the moon, the acceleration due.
Kinematics And other goodies.
Free Fall.
Gravity and Motion Unit 8 Section 1.
Notes Section VELOCITY and ACCELERATION
Lesson 2.3 Falling Objects
Free Fall.
Free Fall Definition: The value of g is:
Free-Fall acceleration
Motion in a Straight Line
Free Fall Free fall: when an object is only affected by gravity
Free Fall Free fall: when an object is only affected by gravity
ACCELERATION.
Calculating Acceleration
Free Fall All bodies accelerate downwards at -10m/s2 on earth regardless of mass (in the absence of air resistance). On the moon, the acceleration due.
Bouncing Ball Physics – Velocity / Acceleration / Displacement
9.1 – Describing Acceleration
Chapter 2 Motion in One Dimension
Chapter 2 Motion in One Dimension
Velocity and Acceleration
2.7 Freely Falling Bodies In the absence of air resistance, all bodies at the same location above the earth fall vertically with the same acceleration.
Calculating Acceleration
Kinematics IV Free Fall motion.
Presentation transcript:

Section 3: Falling Objects Chapter 2 Section 3: Falling Objects

Free Fall acceleration: An object dropped or thrown near the surface of the Earth experiences a constant acceleration directed toward the center of the earth. This acceleration is called the free- fall acceleration, or the acceleration due to gravity. Free fall acceleration is the same for all objects, regardless of mass.

Free fall acceleration: The value we will use for free fall acceleration is: agravity = g = -9.81 m/s2 This is the average value near the surface of the Earth. It is different at other locations, such as on the Moon. We consider the direction of free fall to be negative because it is toward the Earth (down), so we assign a negative value to the acceleration vector (the object accelerates toward earth)

Free fall acceleration: 9.8 m/s 19.6 m/s 29.4 m/s 39.2 m/s 49.0 m/s

Free fall acceleration: All objects, when thrown up will continue to move upward for some time, stop momentarily at the peak, and then change direction and begin to fall. Vertical velocity at the top of the arc is 0

Free fall acceleration: If 2 objects of different masses are dropped from the same height, they will accelerate at the same rate, and hit the ground at the same time (not counting air resistance)

Ignore Air Resistance (unless instructed otherwise) If there is air resistance, the object will be slowed down The more surface area, the more air resistance. An object with the same mass and more surface area will be slower than an object with less surface area. (ex. A wadded piece of paper and a flat piece of paper.) When there is no air resistance, (such as in a vacuum) no matter what the surface area of the object is, it will fall and hit the ground at the same time as all other objects. Unless told otherwise, you can ignore air resistance when working free-fall problems

Formulas Acceleration = 𝑓𝑖𝑛𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 − 𝑖𝑛𝑖𝑡𝑖𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑡𝑖𝑚𝑒 = 𝑣 𝑓 − 𝑣 𝑖 ∆𝑡 (from previous unit) Acceleration = 𝑓𝑖𝑛𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 2 − 𝑖𝑛𝑖𝑡𝑖𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 2 2 (𝑑𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡) = 𝑣 𝑓 2 − 𝑣 𝑖 2 2∆𝑑

Equations for Free-Fall Acceleration When vi = 0 m/s When vi = 0 m/s ∆𝑑 = 𝑣 𝑓 2 − 𝑣 𝑖 2 2𝑎

Formulas (continued) For constant velocity, For accelerated motion, Displacement (d) = 𝑣 ∆𝑡 (from previous unit) For accelerated motion, 𝑑= 𝑣 𝑖 ∆𝑡 + 1 2 𝑎 𝑡 2 For zero initial velocity (for example, free-fall from a drop), 𝑑= 𝑣 𝑖 ∆𝑡 + 1 2 𝑎 𝑡 2 = 0 ∙ ∆𝑡 + 1 2 𝑎 𝑡 2 = 1 2 𝑎 𝑡 2

Class assignment / Homework 1. A gumdrop is released from rest at the top of the Empire State Building, which is 381 m tall. Disregarding air resistance, calculate the displacement of the gumdrop after 1.00, 2.00, and 3.00 s. 2. A small sandbag is dropped from rest from a hovering hot-air balloon. After 2.0 s, how far below the balloon is the sand bag? 3. A physics student throws a softball straight up into the air with a speed of 17.5 m/s. The ball is in the air for a total of 3.60 s before it is caught at its original position. How high does the ball rise? (Hint: The time to max height is ½ total time.)

Average velocity : (slope of the line) Displacement : x position x as a function of time t x2 x x1 t t1 t2 t Average velocity : (slope of the line)