S1W6 Newton's first two laws

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1

This is a position vs time graph. is the man walking faster or slower in the green section compared to the red section?

Green is faster

red is faster

they are the same speed.

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what is the farthest distance the walker gets from his starting point?

3

4

5

6

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A clown is throwing a ball up and down on a railroad platform moving through town. Which of the following is the difference between the frame of reference of someone on the car, vs someone on the ground?

From the ground, the ball is moving straight up and down, from the railroad car, the motion looks like an arc through the air.

From the railroad car, the ball is moving straight up and down, from the ground, the motion looks like an arc through the air.

because the motion of the car is not accelerating, the two perspectives are the same

because the motion of the car is not accelerating, the motions look similar, but both are arcs. the ground perspective arc is just thinner.

1

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which of the following acceleration graph matches the above velocity graph?

Option 1

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Option 2

null

Option 3

null

Option 4

null

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Watch the following video on Newton's first law. do you have any questions?

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Which of these is the best definition of inertia?

How hard something is to rotate

the tendency to resist a change in velocity

A force that acts on all matter

the reason there is a pause before something starts falling

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Mass is simply a measurement of inertia. What is the definition of mass?

How heavy something is

how much something resists acceleration

how much space something takes up

the quantity of molecules making up an object

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Which of the following is a good example of Newton's first law of motion?

a rocket launching into space

a ball rolling down a hill

a car accelerating along a straight road

a book resting on a table

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Some people (such as me) will state newton's first law as a "unbalanced" external force rather than a "net" force. What does unbalanced mean here?

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Read in your physics book the following 56-62, the sections on Newton's first law, mass, and newtons second law of motion. the first two sections should re-ieterate the last video. Focus on the section on the second law. do you have any questions?

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If an object has no acceleration, does that mean there are no forces on the object? explain why or why not?

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What is the difference between weight and mass?

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true/false - and object with mass can have no weight

True

False

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Plug and chug - you are out in space - your engine gives a constant force of 1N. if the rocket has a mass of 100,000 kg, calculate the acceleration. you can use F=MA, (use the hint if you need)

1/100000 m/s^2

1/100000 Nm/kgs^2

100000 kg/n

100000m/s^2

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assume a rocket had a constant acceleration of 0.01m/s^2, Using v=at, what is the velocity of that rockets after 10 days?

v=(0.01)(10)=0.1 m/s

v=(0.01)(10)(24)(60)(60) = 8,640 m/s

v=(0.01)(10)(9.8)(60)(60)=3,528 m/s

v=(0.01)(10)=0.1 m/day

1

A 400 kg bear is grasping a vertical tree slides down at a constant velocity. What is the friction force that acts on the bear?

No friction, because the bear is moving

the force of gravity on the bear is $400kg \cdot -10m/s^2$, we know the friction force = +4000 kgm/s^2 because the sum of forces has to be zero since there is no acceleration

there is no way to tell, because not enough information is given

the friction is 1/100 th the force of gravity in the opposite direction because the bear would be going 10 times faster without it.

1

A 747 jumbo jet of mass 30,000 kg experience in takeoff when the thrust for each of the four engines is 30,000 N. What acceleration does it have?

F=ma, so $30,000N= 30,000kg \cdot a , a=1$

The airplane has four engines, so each engine only has 1/4th the thrust which is 7,500 N. $7,500N =30,000 kg \cdot a, so \\a=1/4$

The airplane has four engines which each have 30,000N, so the total force on the plane is 120,000N.
$120,000N=30,000 kg \cdot a, \\a=4$

There is not enough information

	1 m	4 m/s	-9.8 m/s^2	9.8 m/s^2	5 seconds	3 m	0 m	Variable we are looking for
a
v0
x0
time when it hits
position when it hits

	1 m	4 m/s	-9.8 m/s^2	9.8 m/s^2	5 seconds	3 m	0 m	Variable we are looking for
a
v0
x0
time when it hits
position when it hits

S1W6 Newton's first two laws

This is a position vs time graph. is the man walking faster or slower in the green section compared to the red section?

what is the farthest distance the walker gets from his starting point?

A clown is throwing a ball up and down on a railroad platform moving through town. Which of the following is the difference between the frame of reference of someone on the car, vs someone on the ground?

which of the following acceleration graph matches the above velocity graph?

Watch the following video on Newton's first law. do you have any questions?

Which of these is the best definition of inertia?

Mass is simply a measurement of inertia. What is the definition of mass?

Which of the following is a good example of Newton's first law of motion?

Some people (such as me) will state newton's first law as a "unbalanced" external force rather than a "net" force. What does unbalanced mean here?

Read in your physics book the following 56-62, the sections on Newton's first law, mass, and newtons second law of motion. the first two sections should re-ieterate the last video. Focus on the section on the second law. do you have any questions?

If an object has no acceleration, does that mean there are no forces on the object? explain why or why not?

What is the difference between weight and mass?

true/false - and object with mass can have no weight

Plug and chug - you are out in space - your engine gives a constant force of 1N. if the rocket has a mass of 100,000 kg, calculate the acceleration. you can use F=MA, (use the hint if you need)

assume a rocket had a constant acceleration of 0.01m/s^2, Using v=at, what is the velocity of that rockets after 10 days?

A 400 kg bear is grasping a vertical tree slides down at a constant velocity. What is the friction force that acts on the bear?

A 747 jumbo jet of mass 30,000 kg experience in takeoff when the thrust for each of the four engines is 30,000 N. What acceleration does it have?

This is a position vs time graph. is the man walking faster or slower in the green section compared to the red section?

what is the farthest distance the walker gets from his starting point?

A clown is throwing a ball up and down on a railroad platform moving through town. Which of the following is the difference between the frame of reference of someone on the car, vs someone on the ground?

Plug and chug time. You are on earth and you toss a ball up in the air with the initial velocity of 4 m/s. The ball starts 1 meter from the ground. How long does it take to hit the ground. given the following equation, what do you know?

which of the following acceleration graph matches the above velocity graph?

Watch the following video on Newton's first law. do you have any questions?

Which of these is the best definition of inertia?

Mass is simply a measurement of inertia. What is the definition of mass?

Which of the following is a good example of Newton's first law of motion?

Some people (such as me) will state newton's first law as a "unbalanced" external force rather than a "net" force. What does unbalanced mean here?

Read in your physics book the following 56-62, the sections on Newton's first law, mass, and newtons second law of motion. the first two sections should re-ieterate the last video. Focus on the section on the second law. do you have any questions?

If an object has no acceleration, does that mean there are no forces on the object? explain why or why not?

What is the difference between weight and mass?

true/false - and object with mass can have no weight

Plug and chug - you are out in space - your engine gives a constant force of 1N. if the rocket has a mass of 100,000 kg, calculate the acceleration. you can use F=MA, (use the hint if you need)

assume a rocket had a constant acceleration of 0.01m/s^2, Using v=at, what is the velocity of that rockets after 10 days?

A 400 kg bear is grasping a vertical tree slides down at a constant velocity. What is the friction force that acts on the bear?

A 747 jumbo jet of mass 30,000 kg experience in takeoff when the thrust for each of the four engines is 30,000 N. What acceleration does it have?