Define kinetic energy.
An object that is moving exhibits kinetic energy. An object that is moving quicker has a higher kinetic energy than one that is moving slower.
Define potential energy.
An object that has potential energy has the potential to transform that energy into another form. An object that is placed at a higher elevation has more potential energy than an object placed on a lower elevation.
Define Energy.
An object's ability to work.
Look at the force represented in this image and complete the following:
Force is exerted by: _______________
Force is acting on: _______________
What change does the object experience?
Force is exerted by the athlete.
Force is acting on the javelin.
The javelin starts to move and increases in speed (it accelerates).
Will the light bulbs light up in this image? Explain.
No, the image shows an open circuit. The flow of electrons is absent.
Define Newton's First Law of Motion.
Newton's First Law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. It is seen as a statement about INERTIA, that objects will remain in their state of motion unless a force acts to change the motion.
Define Newton's 2nd Law of Motion.
Newton's Second Law of Motion states that Force equals mass x acceleration. The more force is exerted on an object, the more it will accelerate. Also a same force exerted on a smaller mass will accelerate more.
Define Newton's 3rd Law of Motion.
For every action, there is an equal and opposite reaction. When 2 objects, objects A and B interact with each oter, they exert equal forces upon each other.
What type of energy is stored into a battery? Name 2 other objects that store this type of energy?
Chemical Energy is stored into a battery. Muscles, food, wood, coal, oil, gas also store chemical energy.
In the image below, at what point does the roller coaster cart have the highest value of potential and kinetic energy?
Highest Potential Energy: On top of the first hill
Highest Kinetic Energy: At the bottom of the first hill, at the loop's exit and at the end of the circuit.
Which energy is generated by moving electrons?
Electrical energy is the energy generated by moving electrons.
We want to create 2 teams of 2 members that will exert the same amount of force. Who will be in each team?
Meredith and Sara vs. Juan and Miguel
Draw the forces acting on the surfer and indicate the object exerting them. Draw the arrows from the center of the surfer (see red the red square with a circle in it).
Classify the following materials between electrical insulators and conductors:
copper
plastic
wood
graphite (part of a pencil used to write)
Air
Cotton
Water
Aluminum
Silver
Conductors: All metals such as Copper, Silver, and Aluminum, as well as non metals such water and graphite.
Insulators: Cotton, wood, air, plastic
Name 2 examples of objects that experience inertia.
An object at rest or an object moving in the same direction at a constant speed.
Mr. Sam is skiing. He is not a good skier. If he has a mass of 103 kg, and an acceleration of 14m/s², what is the force Mr. Sam feels when he skis into a tree?
The force Mr. Sam feels is 1442N.
The forces involved in Newton’s third law act ____
a) On the same object
b) On different objects
c) In same direction
d) On five bodies
The forces involved in Newton’s third law act on different objects.
A flashlight is a device consisting of a battery wired to a light bulb. Chemical energy from the batteries is transformed into electric energy in the wires. What form or forms does the electric energy transform into in the light bulb?
The electrical energy is trasnformed into light energy.
Where does a car on a hill have the most potential energy?
Top of the hill.
Name the type of energy defined by splitting uranium atoms to produce heat?
Nuclear fission generates energy by splitting uranium atoms with a neutron.
We want to create 2 teams (one team of 3 and one team of 2) that will exert the same amount of force. Who will be in each team?
Sam and Miguel vs. Juan, Sara and Meredith
Draw the force arrows in the following image (pay extra attention to the arrow size):
A bungee jumper at the pre jump (assume the jumper's feet are still on the ledge) and jump phase.
What type of circuit is shown in this image?
A parallel circuit is shown in the image.
5.
EXPLAIN your reasoning.
1. Balanced forces because the student is at rest. The normal force and gravity are the same and acting in opposite directions.
2. Unbalanced forces because the runner is accelerating. The applied force from the runner is greater than the air resistance.
3. Unbalanced forces because the bears are changing direction. The 2 applied forces are different as they are exerted by 2 different masses. The larger bear exerts more force on the seesaw.
4. Balanced forces because the flowers are at rest. The normal force and gravity are the same and acting in opposite directions.
5. Balanced forces. The applied force is equal to the friction force and there is no acceleration.
Julie kicks a soccer ball with a mass of 0.5 kg. It accelerates with a rate of 5 m/s². Anneta kicks a bowling ball with a mass of 5 kg. It accelerates at 2 m/s². What are the Forces on the two balls? Whose foot do you think hurts more? Why?
Julie kicks the soccer ball with 2.5 N of force. Anneta kicks the bowling Ball with 10 N of force. Anneta's foot probably hurts more. Newton’s third law means the force is acting on the balls, but also on the feet doing the kicking.
1. Two bodies in contact experience forces in ________
a) Same direction
b) Opposite directions
c) Perpendicular directions
d) Five different directions
2. A baseball player hits a ball with a force a 5 N. What force does the bat experience?
a) 5 N
b) 10 N
c) 15 N
d) 20 N
1. Two bodies in contact experience forces inopposite directions.
2. The bat also experiences 5N of force according to Newton's 3rd Law of Motion.
Production and Electricity use the most amount of energy.
Animals and Farming use the least amount of energy.
Indicate the energy source used by each of the following sources of transportation.
Cars
Sail boat
Nuclear Powered Submarine
Cars: Fossil Fuels
Sail boat: Wind
Nuclear Powered Submarine: Uranium or Plutonium
When someone bounces a basket ball, the mechanical energy transforms into which types of energies?
The mechanical energy trasnforms into sound and heat energy.
If Juan and Sarah play against each other, who is going to win? Explain.
What will the net force be like? Explain.
Juan will win. Sara can only exert half of Juan's force. The net force is the difference between Juan's and Sarah's exerted force. The net force will not be as strong as the winner's force.
Draw the force arrows in the following image (pay extra attention to the arrow size):
A bungee jumper at the Stop Phase.
Observe the circuits below:
Which circuit allows for the brightest light bulbs? Explain your reasoning.
The second circuit has the brightest light bulbs because there is more potential energy in the batteries because of the higher voltage.
An object with a mass of 2kg has a force of 4N applied to it. What is the resulting acceleration of the object?
The acceleration is 2m/s2.
Classify the forms of transportation according to whether they use renewable or non renewable energy sources.
Nuclear submarine
Solar Impulse Aircraft
Hot Air Balloon
Bicycle
Car
Airliner
Sail boat
Surf Board
Renewable: Surf Board, Sail boat, Solar Impulse Aircraft, Bicycle
Non renewable: Nuclear submarine, Hot Air Balloon, Car, Airliner
Miniature golf is a game in which players hit a ball into various holes while avoiding obstacles.
What forms of energy do the balls have when they are first hit?
Why do the golf balls end up stopping (think energy, not forces)?
The golf balls have mechanical energy when they are first hit.
The mechanical energy is transferred to the surrounding environment.
1) What factor is different between the two proposed experimental situations?
2) Which of the 2 roller coaster wagons travels the longest distance? Explain.
1) The height from which the wagon is released.
2) The second wagon because it had more potential energy at the beginning. The higher potential energy transformed into a higher amount of kinetic energy once pushed which allowed for the car to travel a longer distance.
Now look at these teams. Who is going to win? Explain.
Since Sam can exert twice as much force as Juan and Juan can exert more force than Miguel and Sara, it is safe to conclude that Sam and Juan will win the tug of war.
1. Which type of charges do these balloons have?
2. Which type of charges do these balloons have?
1. The 2 balloons have opposite electric charges as they attract each other.
2. The 2 balloons have the same electric charge as they repel each other.
1. An object will experience more air resistance when it falls if it has greater
a) gravity
b) weight
c) mass
d) surface area.
2. The fundamental force which holds the planets in their orbits around the Sun is the _____ force.
a) electrostatic
b) centrifugal
c) gravity
d) friction
3. The gravitational force between two objects can cause them to move. If Gerard has two rubber balls and dropped them, which of the following would affect the gravitational force?
a) magnetism
b) shape
c) mass
d) temperature
4. David is conducting an experiment to see how far a marble will roll when he releases it at the top of an inclined plane. Why does the marble speed up as it travels down the inclined plane?
5. Which of the following objects has the greatest gravity?
6. The weight of a person would _____ if the mass of the Earth increased while the radius remained constant.
a) increase
b) decrease
c) stay the same
7. If two objects each have a mass of 10 kg, then the force of gravity between them _______.
8. Why does the Moon orbit Earth?
1. surface area
2. gravity
3. mass
4. The force of gravity pulls the marble down the inclined plane.
5. Sun
6. increase
7. is greater when they are closer together
8. There is gravitational attraction between the Earth and the Moon.
Consider the 3 circuits below. Rank the brightness of the bulbs. Explain your reasoning.
Ranking from most to least bright.
D, E and A have the same brightness.
B and C are half as bright as D, E and A.
Light bulbs B and C are assembled as a series circuit therefore splitting the battery voltage between them. Light bulbs D and E are assembled as a parallel circuit maintaining the same voltage as the battery. Light bulb A has the same voltage as D and E, which is the voltage of the battery.
Find the net force of the following object (assume the units are in N). Identify the direction of the accelerating box.
20N-20N= 0N
13N -6N = 7N
The net force is 7N. The object is moving downwards.
Andrei and his dad are building a racing kart in their garage. the engine they assembled in it allows the kart to go from 0 to 10m/s in 5 seconds. The kart's mass when Andrei is driving it is 167kg.
a) What is the kart's acceleration in m/s/s?
b) What is the force the engine exerts on the vehicle and its occupants?
c) Andrei wants to modify the kart's design so that it can accelerate 4m/s/s. What would be the mass of the faster kart?
a) time speed
0s 0m/s
1s 2m/s
2s 4m/s
3s 6m/s
4s 8m/s
5s 10m/s
acceleration 2m/s/s (10/5=2m/s/s)
b) F = m x a = 167kg x 2m/s/s = 334N
c) m = F / a = 334N / 4m/s/s = 83.5kg, if Andrei wants to double the acceleration, he will have to reduce the kart's mass by half (167kg/2=83.5kg).
In the drawing above:
a. How much force is the physics student exerting on the rope? In what direction?
b. How much force is the wall exerting on the rope? In what direction?
c. What is the net force on the force gauge?
d. Would the Physics student be moving? If yes, is he accelerating?
e. What would happen if the wall stopped exerting any force?
f. What happens if the Physics student is standing on ice?
g. What is the force between the student and the ground called?
h. Draw the arrows on the diagram to represent three sets of force pairs.
a. The Physics student is exerting 500N of force on the rope.
b.The wall is also exerting 500N of force on the rope accordingto Newton's 3rd Law of Motion.
c. The net force is 0N.
d. No, the physics student would be at rest.
e. The student would accelerate backwards.
f. The Physics student will accelerate forwards.
g. Friction is the force between the student and the grund.
h.