Objective 5: IPC Physics

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

A 1-kilogram ball has a kinetic energy of 50 joules. The velocity of the ball is —

F 5 m/s

G 10 m/s

H 25 m/s

J 50 m/s2

2

1mvKE

mvpt

vva

t

dv

if

Velocity equations:

4(A) QUANTITIES AND UNITS

Quantity Symbol Unitmass m kg (kilogram)

time t s (second)

distance x m (meter)

speed or velocity v m/s

momentum p kg-m/s

acceleration a m/s2

work W J (Joules)

power P W (Watts)

A 0.50 kg ball with a speed of 4.0 m/s strikes a stationary 1.0 kg target. If momentum is conserved, what is the total momentum of the ball and target after the collision?

A 0.0 kgm/s

B 0.5 kgm/s

C 1.0 kgm/s

D 2.0 kgm/s

THE LAW OF CONSERVATION OF MOMENTUM states

that:

Total momentum before a collision

Equals

Total momentum after a collision

What is the net force exerted on a 90.0 kg race-car driver while the race car is accelerating from 0 to 44.7 m/s in 4.50 s?F 9.8 NG 20 NH 201 NJ 894 N

Use the formulas for a and F to solve for F.

t

vva

maF

if

Starting from rest at the center of a skating rink, two skaters push off from each other over a time period of 1.2 s. What is the force of the push by the smaller skater?F 16 NG 32 NH 88 NJ 100 N

(4B) Investigate and describe applications of Newton’s laws such as in vehicle restraints, sports activities, geological processes, and satellite orbits

A hockey player pushed a puck toward the opposite side of a level ice rink. The player expected the puck to continue all the way across the ice, but the puck slowed and stopped before reaching the other side. Which of these best explains why the puck failed to slide all the way to the opposite side?F The puck’s temperature changed.G An upward force acted on the puck.H The puck’s momentum remained unchanged.J An opposing force acted on the puck.

Newton’s Laws of MotionNewton’s Laws of MotionLaw of InertiaLaw of Inertia

An object at rest or in motion will stay that way until a force acts

on it.

Law of AccelerationLaw of Acceleration

An object will accelerate when a force acts on it.

Law of Action and ReactionLaw of Action and Reaction

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

(4B) QUANTITIES AND UNITS

Quantity Symbol Unitmass m kg (kilogram)

acceleration a m/s2

force F N (Newtons)

;

The pictures show how an air bag functions in a collision. How much momentum in kg m/s does the air bag absorb from the crash-test dummy if all of the crash-test dummy’s momentum is absorbed by the air bag? Record and bubble in your answer to the nearest whole number on the answer document.

A substance with a lower density will float on a substance with a higher density.

Dice = 0.897 g/mLDwater = 1.00 g/mLDalcohol = 0.802 g/mL

6 3 0

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?F What goes up must come down.G For every action there is an equal and opposite reaction.H The shape and size of an object affect air resistance.J The acceleration due to Earth’s gravity is 9.8 m/s2.

(4D) Investigate and demonstrate [mechanical advantage and] efficiency of various machines such as levers, motors, wheels and axles, pulleys, and ramps.

The Six Simple Machines

(4D) QUANTITIES AND UNITS

Quantity Symbol Unitwork W J (Joules)

mechanical advantage M. A. No unit

efficiency eff No unit

% efficiency % eff %

in

out

W

WEff

out

in

in

out

d

d

F

FAM ..

Which configuration of pulleys and belts shown below will result in the fastest rotation of Spindle 2?

SIMPLE MACHINESThe inclined plane The wheel and axle The lever The pulley The wedgeThe screw

Which of these represents a properly balanced system?

Equilibrium is achieved when:Force X moment arm is equal at both sides of the fulcrum.

Fulcrum: point of rotation

Moment Arm:

distance from

fulcrum

Which lever requires the least effort to lift the load?

EFFORT = FORCEIf the load is closer to the fulcrum than the effort, you need less effort to lift the load.

(5B) Demonstrate wave interactions including interference, polarization, reflection, refraction, and resonance within various materials.

The diagram shows waves approaching a barrier. Which pattern will be formed after the waves pass through the opening in the barrier?

(5B) QUANTITIES AND UNITS

Quantity Symbol Unit

period T s (second)

frequency f Hz (Hertz)

wavelength m (meters)

wavespeed v m/s

fv T

f1

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 PolarizationB ResonanceC ReflectionD Diffraction

Reflection – wave hits a barrier and returns to its origin (bounce)Refraction – bending of light due to a change in medium (bend) Resonance – the tendency of a system to vibrate when excited by its resonant frequency (react)Interference – when two or more waves combine (meet)Polarization –allows only a certain orientation of a transverse wave through (filter)

When a DVD is read, laser light touches the DVD surface and is then measured at location A. What allows light to return to location A after striking the DVD surface?F ConductionG RefractionH MagnificationJ Reflection

An empty cup was tightly covered with plastic wrap, and a few grains of salt were sprinkled on top of the plastic. When a tuning fork was struck and placed slightly above the plastic wrap, the salt began to move. Which characteristic of waves does the movement of the salt best demonstrate?

A Echo formation

B Diffraction

C Resonance

D Specular reflection

(6A) Describe the law of conservation of energy

What is the approximate difference in gravitational potential energy of the two shaded boxes?A 19 JB 39 JC 59 JD 79 J

THE LAW OF CONSERVATION OF ENERGY states that:

The sum of all energies is the same at any point

in the system.

28.9s

mg

mghGPE

(6A) QUANTITIES AND UNITS

Quantity Symbol Unitmass m kg (kilogram)

height h m (meter)

velocity v m/s

gravitational acceleration g m/s2

kinetic energy KE J (Joules)

gravitational potential energy GPE J (Joules)

Fuel cells powered by plankton from the seabed can be used to operate instruments that monitor ocean currents and water temperature. These fuel cells get their energy by converting —F chemical energy to electrical energyG electrical energy to mechanical energyH hydroelectric energy to geothermal energyJ mechanical energy to chemical energy

The temperature of the water increases by 8°C when the metal block is added. Which could cause the temperature of the water to increase by 10°C after the metal block is added?F Using 500 g of waterG Using a large beakerH Adding more 20°C waterJ Adding heat to the metal block

THE LAW OF CONSERVATION OF ENERGY also states

that:Energy must be put into a system to get

energy out of a system.

According to the equation E = mc2, mass —F travels at the speed of lightG can be transformed into energyH contains light energyJ is doubled when exposed to light

6D) Investigate and compare economic and environmental impacts of using various energy sources such as rechargeable or disposable batteries and solar cells.

Which of these is an advantage of producing electricity using solar power plants rather than using coal-fired power plants?A Solar power plants can operate for about 10 hours per day.B Solar power plants can produce variable amounts of energy.C Solar power plants produce fewer pollutants.D Solar power plants require continuous sunlight.

Energy Sources Fossil Fuels (coal, petroleum,

natural gas) Wind Power Wave/Tidal/Hydroelectric Power Biomass (methane) Hydrogen Fuel (Fuel Cells) Solar Power Geothermal Power Nuclear Power

Which of these devices uses the sun’s energy directly?

A Windmill

B Hydroelectric dam

C Nuclear power plant

D Photovoltaic cell

“Photovoltaic" comes from the Greek phos meaning "light", and the name of the Italian physicist Volta, are named. It means literally of light and electricity.

A company has decided to market itself as environmentally friendly. If the company is going to sell calculators, the use of which energy source would produce the fewest by-products and the least waste?

F Rechargeable batteries

G Solar cells

H Dry-cell batteries

J Tesla coils

This picture shows a small section of a solar power plant. Which of these decreases the energy production at such power plants?F Cloudy skiesG Ozone in the airH Hot weatherJ Low humidity

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

The transfer of heat by the movement of air currents in Earth’s atmosphere is an example of —A conductionB convectionC radiationD fusion

Conduction – transmission of heat through matter (solid)

Convection – transmission of heat through currents (fluids). Warm, low density fluid rises, cool, high density fluid sinks.

Radiation – emitting energy as waves or particles. (No medium required.)

(6B) QUANTITIES AND UNITS

Quantity Symbol Unit

mass m kg (kilogram)

specific heat cp J/kg-K (Joules per kilogram-Kelvin)

change in temperature ∆T K (Kelvin)

heat gained or lost Q J (Joules)

TmcQ p

In winter the air just above the top bunk of a bunk bed is warmer than the air just above the bottom bunk because warm air rises. Which of the following describes the method of heating that causes this difference intemperature?F Radiation from the roomG Heat transfer through the wallsH Convection currents in the roomJ Heat conduction through the bed

Which of these is the best example of heat transfer by radiation?A A satellite is warmed by sunlight.B Butter melts on warm bread.C A ceiling fan cools a warm room.D Puddles of water cool a warm tile floor.

A man who was sleeping wakes up because he hears the smoke alarm go off in his house. Before opening the bedroom door, the man feels the door to see whether it is warm. He is assuming that heat would be transferred through the door by —A conductionB convectionC radiationD compression

THE END