Дидактические материалы для работы с учебным пособием С.В. Андриановой «English Thesaurus of Student-Physicist». Учебно-методическое пособие
.pdf10.Will an object's velocity be changing if an object in equilibrium is still moving? (No.)
11.How is the force of gravity known otherwise? (weight)
12.How do we measure weight? (in Newtons)
13.Give an example of a net force making something moves. (the gravitational force)
14.What force is explained by Newton's third law? (normal forces)
15.State the third law. (For every action there is an equal but opposite reaction.)
16.What does it mean? (If you exert a force on an object it exerts an equal force back to you.)
17.What does "a normal force" mean? (perpendicular)
18.Can normal force change its magnitude? (Yes.)
19.What do we draw to represent forces? (arrows)
20.What equation shows the value of acceleration? (a is equal to the difference between the weights or the net force on the system divided by the total mass)
Exercise 3. Give examples of inertial effect in our everyday life. (braking distance, sliding)
Exercise 4. Are the following statements true (T) or false (F)?
Force is a vector quality. (T)
If an object’s velocity isn’t changing in either magnitude or direction, then its acceleration must be zero. (T)
Mass doesn’t affect acceleration. (F)
The acceleration of an object is proportional to its mass.
(F) /inversely proportional/
There is the universal gravitation constant. (T)
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Exercise 5. Give your comments on the following statement:
Newton’s laws provide an excellent description of nature. Why? What are the limits of their application?
Unit 5
ENERGY
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=w4QFJb9a8vo
Exercise 2. Answer the questions:
1.What most important principle in physics was mentioned in the video? (conservation of energy)
2.What happens when you apply a force over a certain distance? (We do work.)
3.What was meant by "system"? (whatever section of the universe you are talking about at the time)
4.What is the amount of work equal to? (to the force you're using to do the action times the distance)
5.What unit is work expressed in? (Joules [u:].)
6.What is the equation for work? (It is equal to force times distance, times the cosine of theta /thi:ta/.)
7.Why do we need angle? (to fit any scenario that involves a constant force being applied over a certain distance)
8.What if a force isn't constant? What happens? (We'd have to count up the amount of force we applied over each part of distance.)
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9.What is a fast way to add together increments? (integration)
10.Can we say that work is change in energy? (Yes.)
11.How is work defined? (It's what happens when an external force is applied to a system and changes the energy of that system.)
12.How is energy defined? (the ability to do work)
13.What is kinetic energy? (energy of motion)
14.Give us an example when there is no kinetic energy. (a box resting on the ground)
15.What is potential energy? (It's potential work. Energy that could be used to do work.)
Exercise 3. Read the formula: /Work is equal to force times distance times the cosine of theta/
Exercise 4. Are the following statements true (T) or false (F)?
Energy is present in the Universe in a variety of forms. (T)
The total amount of energy in the Universe never changes.
(T)
The work is done if an object is moved through some displacement while a force is applied to it. (T)
An object with kinetic energy cannot do work on another object. (F)
The spring force is conservative. (T)
Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history
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of the invention; the way and prospects of using; being ecological-friendly etc.:
Which is the most promising kind of energy? Why? What do you know about renewable sources of energy?
Unit 6
MOMENTUM AND COLLISIONS
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=Y-QOfc2XqOk
Exercise 2. Answer the questions:
1.What qualities do we have to take into account to figure out what's happening when objects collide? (momentum and impulse)
2.What does the second Newton's law say? (The net force on an object is equal to its mass times its acceleration.)
3.What is the net force equal to? (the change in the mass times velocity over time)
4.What is momentum? (an object's tendency to remain in motion; an object mass times velocity)
5.What effects collisions between objects? (Momentum is one factor.)
6.What is impulse? (another quality of a collision, change in momentum)
7.What is impulse usually represented by? (a J – the integral of the net force on an object over time)
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8.Can impulse be a way to describe a crash? (Yes.)
9.What types of collision do you know? (elastic and inelastic)
10.Is kinetic energy conserved in elastic collisions (in the conservative systems)? (Yes.)
11.What about inelastic collisions? Is kinetic energy conserved? (No.)
12.What happens to the momentum of the system? (It is always conserved whatever collision it is.)
13.What law says that every action has an equal and opposite reaction? (Newton’s third law.)
14.Why is it important to describe where the center of mass is? (Objects move differently if mass is distributed unevenly.)
15.What is the center of mass? (It’s the average position of all the mass in the system.)
Exercise 3. Read the formula: (Momentum is mass times velocity.)
Exercise 4. Are the following statements true (T) or false (F)?
Linear momentum is the product of mass and velocity. (T)
Changing the momentum of an object doesn’t require the application of a force. (F)
The impulse of the force acting on an object equals the change in momentum of that object. (T)
In an isolated system the total momentum of the system just before the collision equals the total momentum just after the collision. (T)
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In an inelastic collision, both momentum and kinetic energy are conserved. (F) /not kinetic energy/
Exercise 5. What do you know about the history of the invention of an eye pressure tonometer? What other practical application of collision can you think of? Games, medical appliances, models, devices.
Unit 7
ROTATIONAL MOTION AND THE LAW OF GRAVITY
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=fmXFWi-WfyU
Exercise 2. Answer the questions:
1.What do we use to describe rotational motion to compare to translational motion? (It still involves position, velocity and acceleration, but instead of position we use angles, instead of points on a line we follow points along an arc.)
2.What is one of the main units of rotational motion? (a radian)
3.What is it (radian) based on? (on the radius of a circle)
4.What does it describe? (How much of that circumference is covered by a given angle.)
5.How can we convert degrees in radians? (multiply the degrees times /pai/ and divide by 180)
6.How to describe rotational velocity? What is it? (a measure of an object's change in an angle)
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7.What letter is it represented with? (Omega.)
8.What is the formula of angular velocity? (the derivative of angular displacement with respect to time)
9.Can we describe an object's rotation in terms of its tangential velocity? (Yes.)
10.What is angular acceleration? (It is the derivative of angular velocity.)
11.What letter is it represented by? (lower case alpha)
12.What does it describe? (How an object's angular velocity is changing over time.)
13.In how many ways can each point of a rotating object accelerate? (As an object rotates, each point on it can actually accelerate in two different ways.)
14.Is radial acceleration the same as centripetal acceleration? (Yes.)
15.What is it equal to? (It’s equal to the angular velocity, squared, times the radius.)
Exercise 3. Read the formula: (2, times pi, times the circle’s radius) Do you remember what formula it is? (It is the formula of the circumference of a circle.)
Exercise 4. Are the following statements true (T) or false (F)?
Angular quantities must be measured in radians. (T)
For circular motion at constant speed, the acceleration vector always points towards the centre of the circle. (T)
Tangential and centripetal components of acceleration are parallel to each other. (F) /perpendicular/
Every point on the rotating object has the same angular speed. (T)
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Angular variables are closely related to linear variables.
(T)
Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history of the invention; the way and prospects of using; being ecological-friendly etc.:
The generalization of gravitational potential energy and energy conservation offers an easy route to planetary escape speed. Why is it important? Have you read any books/seen any films about interplanetary travelling? Tell us about them.
Unit 8
ROTATIONAL EQUILIBRIUM AND ROTATIONAL
DYNAMICS
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=b-HZ1SZPaQw
Exercise 2. Answer the questions:
1.What is the reason of the fact that not all the objects get the bottom of the ramp at the same time? (Energy is distributed in a rolling object differently.)
2.What are the qualities of rotational motion? (torque, moment of inertia)
3.What force is perpendicular to the axis of rotation? (torque)
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4.What does torque do? [1) Changes an object's angular velocity. 2) Makes things rotate faster/slower.]
5.What factors apply torque? [1) the strengths of the force; 2) distance between force and axis of rotation radius; 3) the angle between the applied force and the radius.]
6.If the radius is larger will torque be more or less? (more)
7.What letter represents torque? (Greek /tau/.)
8.What is the net torque on an object equal to? (its angular acceleration times the moment of inertia)
9.How can we calculate the moment of inertia? (It's the sum of all the individual points of mass of object times the square of the distance from the axis of rotation.)
10.What does the moment of inertia relate to? (mass)
11.What do torques and forces have in common? (the ability to do work)
12.How can we calculate the work done by a torque? (It's the integral of that torque over a certain angle.)
13.Is it true that the more torque you apply the more work you do? (true)
14.What happens to kinetic energy if an object goes without rotating? (All of it goes into translational motion.)
15.What is angular momentum equal to? (to an object's moment of inertia times its angular velocity)
16.Can you create or destroy angular momentum? (No. It always has to go somewhere.)
17.Why was the book the first on the ramp? (All of its potential energy will be covered to translational kinetic energy.)
Exercise 3. Read the formula: (the kinetic energy of translational motion is equal to half of the object’s mass, times its velocity squared.) What formula is it? (the kinetic energy of translational motion)
Exercise 4. Are the following statements true (T) or false (F)?
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Torque relates to an object’s angular acceleration and its moment of inertia. (T)
If an object is in equilibrium the net external torque is zero. (T)
The net torque acing on an object is equal to the time rate of change of the object’s angular momentum. (T)
Angular momentum of an isolated system doesn’t remain constant. (F)
When the force causes the object to rotate counterclockwise, the torque on the object is negative. (F) /clockwise/
Exercise 5. Give your comments on the following statement, speak about advantages/disadvantages; your attitude; history of the invention; the way and prospects of using; being ecological-friendly etc.:
Why does the point of application of a force matter? Where can we use the concepts of rotational equilibrium and rotational dynamics? (They can tell us how the forces affect an object’s equilibrium and rate of rotation. Micro-, macro-levels: architecture, pulsars etc.)
Unit 9
SOLIDS AND FLUIDS
Exercise 1. Follow the link and watch the video:
https://www.youtube.com/watch?v=b5SqYuWT4-4
Fluids in motion: https://www.youtube.com/watch?v=fJefjG3xhW0
Exercise 2. Answer the questions:
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