TEK 4A: Calculate speed, momentum, acceleration, work and power in systems such as in the human body, moving toys and machines.

TAKS Objective 5

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For questions with numbers, remember

• Read the question.• Identify the question word. (What is..., How

much..., etc. • Pick a Formula from the chart.• Solve the problem. Use your

CALCULATOR!

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Motion can be described asMotion can be described as• a change in an object’s

position• Average velocityvelocity (speed) is

the change of position of an object over time

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4 The diagram represents the total travel of a teacher on a Saturday. Which part of the trip is made at the greatest average speed?

F QG RH SJ T

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AccelerationAcceleration is a change in an object's velocity (speed or direction)

• When an object’s speed is changing with respect to time, it is acceleratingaccelerating

aΔvΔt

=v f v i-

Δt=

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What was the garbage truck’s acceleration

between 1 and 5 seconds?A. 1.0 m/s 2B. 1.2 m/s 2C. 4.0 m/s 2D. 6.0 m/s 2

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MOMENTUMMOMENTUMMomentum depends on both velocity and mass of an object.

For an object moving in a straight line, momentummomentum is calculated by multiplying an object’s mass by its velocitymultiplying an object’s mass by its velocity..

momentum = mass x velocity

p m v=

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Which bike rider has the greatest momentum?

A A 44 kg person riding at 45 km/hB A 60 kg person riding at 35 km/hC A 68 kg person riding at 25 km/hD A 70 kg person riding at 15 km/h

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Work

• Work: using a force (a push or pull) for a certain distance

• The work done by forces on an object = changes in energy for that object.

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Machines use power

• Power is how fast you do work. If you work faster, you use more power.

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A mechanic used a hydraulic lift to raise a 12,054 N car 1.89 m above the floor of a garage. It took 4.75 s to raise the car. What was the power output of the lift?

A. 489 W B. 1815 W C. 4796 W D. 30,294 W

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Newton’s Laws1. Objects at rest tend to stay at rest until acted on by an external force. Objects in motion tend to stay in motion until acted on by an external force, Also known as Inertia.

2. Force is equal to mass times acceleration.

3. For every action, there is an equal and opposite reaction.

F m a=

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The illustration above shows a student about to throw a ball while standing on a skateboard. Which illustration below correctly shows the skateboard’s direction of motion after the student releases the ball?

A B C D

A B

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When the air is released from a balloon, the air moves in one direction, and the balloon moves in another direction. Which statement does this situation best illustrate?

A. What goes up must come down. B. For every action, there is an equal and opposite

reaction. C. The shape and size of an object affect air resistance. D. The acceleration due to Earth’s gravity is 9.8 m/s2.

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Which of the following is directly proportional to an object’s mass?

A. The object’s speedB. The temperature of the object in the solid

phaseC. The amount of time the object moves when

pushedD. The object’s inertia

Conservation LawsConservation LawsConservation of Energy – Energy is neither Conservation of Energy – Energy is neither

created, nor destroyed.created, nor destroyed.

Conservation of Momentum – Momentum is Conservation of Momentum – Momentum is neither created, nor destroyed.neither created, nor destroyed.

Conservation of Mass – Mass is neither Conservation of Mass – Mass is neither created nor destroyed.created nor destroyed.

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According to the law of conservation of energy —A energy can both be created and destroyedB energy cannot be created or destroyed, but it

can be changed into different formsC energy cannot be created, but can be

destroyedD energy can be created, but not destroyed

TEKS:5A-D: The student knows the effects of waves on everyday life.

TAKS Objective 5

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2 Basic Types of Waves:Transverse waves have displacements that are

perpendicular to the direction of travel.

Longitudinal waves have displacements parallel to the direction of travel.

Frequency – How many times a wave repeats itself in one second.

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Wave CharacteristicsWavelength (, The length a wave needs

to complete one full cycle)Amplitude

(height, measured from the middle of

the wave to a crest or trough)

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Compressional: matter in medium moves in the same direction as the wave travels; aka: longitudinal

Like… Sound waves

Similarities?

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How do waves differ?How do waves differ?

1) Energy; 2) Velocity; 3) Appearance

TRANSVERSE

COMPRESSIONAL

vs.

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What does Q and S represent in the diagram?

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At 0°C sound travels through air at a speed of 330 m/s. If a sound wave is produced with a wavelength of 0.10 m, what is the wave’s frequency?F 0.0033 HzG 33 HzH 330 HzJ 3300 Hz

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A wave with a 2.2 m wavelength travels 21 m to a wall and back again in 8 seconds. What is the frequency of the wave?

A 1.2 HzB 2.2 HzC 5.7 HzD 369.6 Hz

TAKS 5 TEKS IPC 5A

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Wave Phenomena• Interference – Waves add together or cancel each

other out. • Resonance – One wave causes something else to

vibrate in a similar manner.• Doppler Effect – Changes in frequency based on

motion.• Reflection – A wave bounces off something• Refraction – A wave bends because of a change in

medium.• Diffraction – A wave bends due to interaction with an

edge (or multiple edges). • Polarization – The direction of vibration of a wave.

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H

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1. The diagram above shows waves approaching a barrier. Which pattern will be formed after the waves pass

through the opening in the barrier?(A)(B)(C)(D)

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A guitar player is seated next to a piano. The piano player strikes an E key on the piano. The guitarist reports that this causes the E string on his guitar to vibrate. What is the name of this phenomenon?

A ResonanceB PolarizationC ReflectionD Diffraction

TEK 6B: Investigate and demonstrate the movement of heat through solids, liquids, and gases by convection, conduction, and radiation.

TAKS Objective 5

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Heat- Transfer of Thermal Energy

1. Conduction-objects touching (solids)2. Convection- heat transfer through motion of currents in a gas or liquid 3. Radiation- electromagnetic waves transfer heat; occurs even in a vacuum (empty space).

Three forms of heating:Three forms of heating:

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The primary way liquids and gases transmit heat is by the process of —

F reflectionG conductionH radiationJ convection

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Which of these best explains why skin is warmed by radiant energy?A Sunlight absorbed by the skin increases the skin’s thermal energy.B High-frequency radiant energy is composed of waves with short wavelengths.C Uneven heating produces convection currents within the skin.D Atoms with loosely held electrons transmit heat by conduction.

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Heat convection occurs in gases and liquids. Heat convection does not occur in solids because solids are unable to —

A absorb heat by vibratingB transfer heat by fluid motionC emit radiation by reflecting lightD exchange heat by direct contact

TEK 6F: Investigate and compare series and parallel circuits. 10th GRADE TAKS ONLY slides 36-39.

TAKS Objective 5

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Current Flows in Closed Loops

• No electricity will flow in an incomplete or open loop.

• Current will flow through closed loops.

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Ohm’s Law• Ohm's Law deals with the relationship

between voltage and current in a circuit.

• Ohm's Law is given by:

V R

IVoltage (V) can be thought of as the force pushing electric charges along a conductor

Resistance (R) is a measure of how difficult it is to push the charges along.

Electric current (I) is the movement of electric charge in a conductor.

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21 The diagrams above represent twocomplete circuits. A 9-V battery isconnected to two light bulbs as shown.Which statement best describes what canbe observed?

A One of the lightbulbs in Circuit A willcontinue to shine if the other one goesout.

B One of the lightbulbs in Circuit B willcontinue to shine if the other one goesout.

C The light from Circuit A will be dimmerbecause each light bulb has a directpath to both poles of the battery.

D The light from Circuit B will be dimmerbecause each light bulb must share itscurrent with the other light bulb.

Series Circuit- if one bulb goes out it stops the circuit

Parallel Circuit- the current can branch and continue to light up the remaining bulbs if one bulb goes out