Center of Gravity

Located at center of mass

What happens if the CG extends beyond its base?

The object will topple over.

Where does an object rotate?

It follows a straight line, the center of gravity stays on the line.

What is torque?

Force in a rotating path (circular motion)

What is the formula in order to find torque?

Force x Lever Arm Distance

What is the formula for balancing torque?

Force x Distance / Distance

What happens if you add length onto an object. (Adding length to a wrench) 

There is greater torque produced when the force and lever arm are large.

Rotational Inertia

An object that can move in an arch or circle.

Rotational inertia depends on the distance of mass from the what?

Axis. 

(Harder to rotate weight when weights are further from the center)

What rolls faster? A solid or hollow wheel?

A solid. More mass

What happens when you're in the air and you pull your body closer?

You spin more/ go faster

What is the equation for pressure?

pressure= force/area

What is pressure?

A force acting on a specific amount of surface area.

Given the length of the weightless beam to be 120 inches, and the weight at A to be 600 pounds with the center of gravity to be located 4 feet to the right of A. Find the weight necessary to produce equilibrium at B.

400

The more area the ______ pressure?

Less

An industrial container is holding 200N of water. The area of the inside of the bottom of the container is 2 square meters. What is the pressure?

100

What is a substance that flows and exerts pressure?

Fluids

Rotational Inertia

The resistance an object has to change in its rotational state of motion is called rotational?

Inertia (rotational inertia)

A 5000N car is lifted by a hydraulic piston of an area 2000 square cm. How much force on a 20 square cm piston is needed to lift the car? 

50 N

If you put a rock into a glass of water what happens?

The water in the glass will rise because the stone replaces the water.

 If an object has a density greater than the density of water, what happens to the object?

It sinks.

What is buoyancy?

The apparent loss of weight of objects when submerged into a liquid.

The weight of a floating object equals the weight of what?

The water displaced by the submerged part.

Rock (something heavier than water) 

Wood (something lighter than water)

Fish (equal to water)

Pascal's Principle

Changes in pressure at any point in an enclosed fluid at rest are transmitted undiminished to all points in the fluid and act in all directions.

Bernoulli's Principle

When the speed of a fluid increases,the pressure drops.

What are the 3 mechanics?

Buoyancy, hydraulics, pressure

What are the 4 dynamics?

Aerodynamics, Hydrodynamics, Bernoulli's principle, Traffic engineering

What is the average Kinetic Energy of all particles? 

Temperature

Is there more kinetic energy in a bathtub of warm water or small cup of high temperature?

the bathtub

The transfer of thermal energy is what?

Heat

What is thermal contact?

When heat flows from one object to another.

Absorb, hold, transfer Thermal Energy

CsP (specific heat capacity)

The heating process occuring by currents in a fluid is...

Convection

(without direct contact) 

What type of thermal energy transfer requires a physical contact?

Conduction

(high to low)

Radiation

Through no medium.

electromagnetic energies.

emitted from a source that transfers energy from high to low through a vaccuum.

What are the 3 thermal energy transfers?

Conduction, convection, radiation

What is a conductor?

What is an insulator?

Conductor- Transfers heat quickly

Insulator- Transfers heat slowly

Newton's law of heating/cooling

change in temperature.

An object will become the same temperature as surroundings.

How fast/slow something will heat up/cool down.

Equation for Calories

Mass x Change in Temperature

Transverse Wave

Transports energy by vibrating matter perpendicular to the energy direction.

|---energy

matter             

Longitudinal Wave

Transports energy by vibrating matter parallel to the energy direction.

--> matter

--> energy

Wave Speed Formula

Wave length (lambda) x Frequency

Name a kind of wave that isn’t a transverse wave.

longitudinal wave - sound wave is an example of this

Taking 10g of water and increasing the temperature by 56 degrees requires how many calories of energy?

560

 When two or more waves are at the same place at the same time, the resulting effect is called what? 

Interference

The distance between successive, identical parts of a wave is called its?

Wave length

What is the change in frequency due to motion of a wave source? 

The doppler effect

(like a firetruck wizzing by and it sounds differently once it passes)

What scale is used to measure the intensity of sound?

Decibels

What is force at its natural vibration?

Resonance

(think of gel on drums)

The energy that travels in a wave that is partly electric and partly magnetic.

Electromagnetic Wave

(infared,gamma,UV)

What radiation is the highest frequency on the electromagnetic spectrum?

Gamma

What is the electromagnetic scale?

Low                                                       High

Radio  Micro  Infared  VL  UV X-Ray Gamma

What is transparency?

It allows the energy to get through (glass) or distorts energy as it gets through

(plastic, shower doors)

What is an object that absorbs light and casts a shadow?

Opaque (wood or stone)

What are the color frequencies?

Red, Orange, Yellow, Green, Blue, Violet

If 2 polarized light filters are over lapping at right angles, how much light is getting through? 

Little to no light

What can sound waves not travel through?

A vaccuum

What is the term for the opposition to motion caused by air in aerodynamics? 

Air resistance

What is polarization?

Waves that are transverse.

(polarized glasses block out one direction of a polarized light wave)

The study of the properties of moving air, and especially of the interaction between the air and solid bodies moving through it is?

Aerodynamics

The branch of science and technology concerned with the conveyance of liquids through pipes and channels, especially as a source of mechanical force or control is?

Hydraulics