250 likes | 480 Vues
Quarterly Review April 2014. What factors cause an object to accelerate?. A measure of the change in velocity during a period of time. Increase Speed Decrease Speed Change direction.
E N D
Quarterly Review April 2014
What factors cause an object to accelerate? A measure of the change in velocity during a period of time. Increase Speed Decrease Speed Change direction
John took a trip. He traveled 50 miles in the first hour and only 20 miles in the next hour due to traffic. What was John’s average speed? Show work!
Define Newton’s Law’s • First Law– • Example - An object at rest tends to stay at rest and an object in motion tends to stay in motion unless acted upon by an unbalanced force. When a person slams on their brakes and their shopping bag flies forward in the car.
Define Newton’s Law’s • Second Law– • Example – The acceleration of an object is equal to the net force exerted on the object divided by the object’s mass. If you kick a soccer ball and bowling ball with the same force, the soccer ball will accelerate faster. (It has less mass)
Define Newton’s Law’s • Third Law– • Example – For every action there is an equal and opposite reaction. Gas molecules push down and the rocket launches upward.
What is the force that allows electrons to spin in a circle around the nucleus? Centripetal force
motion Kite stuck in tree, Ball on top of a hill Fossil fuels, food, Gasoline, petroleum electromagnetic
particles system echolocation vibration disturbance
power plant, Fusion (takes place in the sun, fission current object’s height
When hitting a pop fly to the center fielder in a baseball game. At which point does the ball have the most Gravitational Potential Energy? • If the ball was hit with a force of 50 Newton’s and travelled a distance of 90 meters. How much work was done on the ball? The highest point (or the furthest distance from Earth’s surface)
Explain the difference between an energy transfer and an energy transformation. • Energy Transfer - • Energy Transformation – the passing of energy from one object to another object the changing of energy from one form of energy to another form of energy.
During the second marking period you built an egg transporting safety device that was dropped from the top of Kawameeh middle school. Identify the energy transformation that occurred in this process. • GPE >>Kinetic Energy >>Thermal Energy
Energy cannot be created or destroyed • The law of conservation of energy tells us that • Because of this law we can assume that all of the energy in the world Stays the same (remains constant)
Chapter 4 • Identify how frequency and wavelength are related. The lower the frequency, the longer the wavelength
Chapter 5 • 1. A polar bear has thick fur. This helps the bear keep heat inside. The fur is an example of an ____________. • 2. Using the term specific heat explain why you go to the beach in the summer and the sand is extremely hot, but the water is still fairly cold. insulator • At the beach the sand always feels hotter than the • water. Water has a high specific heat, therefore it takes longer to heat up whereas the sand has a low specific heat and it heats up quickly.
Touching a hot iron Conduction Heat is transferred by the movement of currents within a fluid (liquids or gases). Hot air rises, cold air sinks. Convection The transfer of thermal energy from one material to another by electromagnetic waves. Sun warming beach
When you walk outside on a cold winter day explain why your body temperature starts to become cooler. • When you walk outside on a cold day the thermal energy from your body moves to the air around you causing your body temperature to become cooler.
The picture below shows three images of a balloon. Picture B indicates the balloon size at room temperature. Identify what happens in Picture A and Picture C. Balloon C • Warmer temperature • Faster particle movement • Particles are farther apart • Thermal Expansion Balloon A • Colder temperature • Slower particle movement • Particles are close together • Thermal Contraction A B C
Solid Gas Farther than a solid, closer than a gas Very little attraction; particles are far apart Definite volume Definite volume
Melting, vaporization, sublimation • During what phase changes is thermal energy gained? • During what phase changes is thermal energy released? • What happens to temperature during all phase changes? • Explain what surface tension is and give an example. Freezing, condensation, deposition Remains constant Uneven forces acting on the particles on the surface of a liquid. Pepper floating on top of the water.
Using the lines below draw a phase change chart. Your chart should include the following parts: Labels on the X and Y axis, 3 states of matter, 4 phase changes
Use the Venn Diagram to compare and contrast Charles’ and Boyle’s Laws
The gas in a balloon occupies 2.25L at 298 K. At what temperature will the balloon expand to 3.5 L?
Identify the number of protons, neutrons and electrons in the element below. • Protons _______ • Neutrons _______ • Electrons ________ 82 Lead 82 Pb 207 125 82