How Things really Work The Physics behind Everyday

LifeJuly 7 and 9

Overview

Safety First!!

Basic Learning Objectives:

• Learn how to think deeply about both simple and complex things• Understand the difference between Science and Technology • Understand the difference between Education and Training• Realize that it engaging your mind in what surrounds (really observing )

How Things really Work The Physics behind Everyday

LifeTues July 7: Morning Session

9 – 11:30 AM .

Gravity - General Physics/Mechanics Learning Objectives: •Understand the difference between weight and mass.•Understand the basic concept of a "force" •Understand how the force of gravity influences the motion of a projectile•Gain an understanding of the conservation law energy

Online equation calculator:http://physics.webplasma.com/e_solver.html

General Theory: • During this session we will have activities that relate to the branch of physics know as

mechanics. Mechanics is the branch of Physics dealing with the study of motion. No matter what your interest in science or engineering, mechanics will be important for you - motion is a fundamental idea in all of science.

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• To cause anything to change its motion requires a force. Energy is the physical quantity that describes the amount of work that can be performed by a force. Forces and the resulting energy come in many forms, such a motion (mechanical), light, heat (thermal), chemical, electrical, sound, etc. But there are only four fundamental forces, Gravitational, electromagnetic, weak nuclear and strong nuclear. All the forces we experience are cause by on or a combination of the four fundamental forces. Most of what we experience in terms of energy changes in our every day life are actually only the result of two of the fundamental force, gravitational and electromagnetic.

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• We will be examining various situation in which either the gravitational and/or the electromagnetic forces are important. This morning we will be focusing on motion and gravity (i.e. mechanics).

Lab 1: (from Lab 101 Exp 3) - Speed, Velocity and Acceleration• Speed (v) is how fast something moves (change in its

distance from a starting place) over a certain amount of time, v = Δd/Δt

• → → →• Velocity (v) is the objects speed plus its direction, v =

Δd/Δt (→ means it has direction)• →• Acceleration (a) is an objects change in velocity over a

certain amount of time, • a = Δv/Δt + direction• https://

www.msu.edu/~brechtjo/physics/airTrack/airTrack.html

Photogate Gate 1

Photogate Gate 2

tt = T - 1/2 t1 + 1/2 t2

T

t

1

t2

h

Lab 2: (from Lab 101 Exp 6): Newton's Second Law

• Theory: Newton's second law of motion describes the behavior of objects for which all existing forces are not balanced.

• Newton's second law in equation form is Fnet = ma

Lab 3: (from Lab 101 Exp 7): Conservation of Momentum

• Theory: In this Lab we will look at two quantities of motion:– Momentum and Kinetic energy.

• Moving objects have momentum. Intuitively, we know that the bigger an object is and the faster an object moves, the more momentum it has. – Momentum is a measure of how hard it is to stop a moving object. – In the absence of external forces, the total momentum after the collision

equals the total momentum before the collision. This is called the Law of Conservation of Momentum.

• Momentum is defined as the product of mass and velocity. We use the symbol p for momentum. – p=mv.

There are three types of collisions:

•(1) Totally Elastic - the carts (objects) don't stick together and all KE is conserved KEi = KEf.

• (2) Totally Inelastic - the carts (objects) stick together and KE is NOT conserved KEi KEf.

• (3) Partially Elastic - the object carts don't stick together but KE is NOT conserved KEi KEf.

Lab 4: (from Lab 101 Exp 8): Ballistic Pendulum

• The following are the relationship (equation) we will need to solve for the speed

Where where vo is the speed of the ball at time t = 0, the mass of the ball be m, and the mass of the pendulum be M, g is the acceleration due to gravity 9.8 m/s2 and h is how high the pendulum was lifted (h2 - h1)

Using the ballistic pendulum to measure free fall (Figure 7), the relationship that is used is:

• Where D is the range of the ball traveled in the x direction, and H is the height of the table.