What Are Some Basic Newtonian Problems?

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In summary, the conversation was about reviewing basic physics questions and providing helpful hints for someone with a rudimentary understanding of physics. The questions covered topics such as acceleration, forces, and gravity. The questions included multiple choice answers and the correct answers were marked with an asterisk. One question also had a follow-up question asking about the effect of standing on top of a very tall ladder. The conversation ended with a reminder not to post duplicate questions in multiple forums.
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Please review the correctness of these basics physics questions. Add any comments or helpful hints to help my rudimentary understanding. I am truly a "physics novice." Thanks.

Physics Problems – Round 2


1. An object moves with a constant speed of 20 meters per second on a circular track of radius 100 m. What is the acceleration of the object?

a. zero
b. 0.4 m/s/s
c. 2 m/s/s
d. 4 m/s/s*

2. What force is needed to make an object move in a circle?

a. kinetic friction
b. static friction
c. centripetal force*
d. weight

3. A car goes around a curve of radius r at a constant speed. What is the direction of the net force on the car?

a. toward the curve's center*
b. away the curve's center
c. toward the front of the car
d. toward the back of the car

4. If a car goes around a curve at half the speed, the centripetal force on the car is:

a. four times as big
b. half as big
c. one-fourth as big*

5. According to Newton, the greater the distance between masses of interacting objects, the:

a. less the gravitational force between them
b. more the gravitational force between them
c. less the force by the square of the separation distance*
d. none of these





6. If the radius of Earth somehow decreased with no change in mass, your weight would:

a. increase*
b. not change
c. decrease
7. The force of gravity acting on you will increase if you:

a. burrow deep inside the planet
b. stand on a planet with a radius that is shrinking
c. both of these*
d. none of these

8. A hollow spherical planet is inhabited by people who live inside it, where the gravitational field is zero. When a very massive ship lands on the planet’s surface, inhabitants find that the gravitational field inside the planet is:

a. still zero
b. non-zero, directed toward the spaceship*
c. non-zero, directed away from the spaceship

9. A very massive object A and a less massive object B move toward each other under the influence of mutual gravitation. Which force, if either, is greater?


a. The force on A
b. The force on B
c. Both forces are the same*

10. A woman who normally weights 400 N stands on top of a very tall ladder so she is one Earth radius above the Earth’s surface. How much does she weigh there?

a. zero
b. 100 N*
c. 200 N
d. 400 N
e. none of these
 
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1. What are the basic principles of Newtonian mechanics?

The basic principles of Newtonian mechanics are based on three laws proposed by Sir Isaac Newton in his work "Philosophiæ Naturalis Principia Mathematica". These laws state that objects will remain at rest or in a state of uniform motion unless acted upon by an external force, the force applied to an object is equal to its mass times its acceleration, and for every action, there is an equal and opposite reaction.

2. How do you solve a basic Newtonian problem?

To solve a basic Newtonian problem, you first need to identify the forces acting on the object in question. Then, using Newton's second law of motion, F=ma, you can calculate the net force and acceleration of the object. Finally, using Newton's third law of motion, you can determine the reaction force to the original force applied to the object.

3. What is the difference between static and kinetic friction?

Static friction is the force that keeps an object at rest when a force is applied to it, while kinetic friction is the force that acts on an object when it is in motion. Static friction is typically greater than kinetic friction, as it takes more force to overcome the initial resistance of an object at rest.

4. How does Newton's third law of motion apply to everyday situations?

Newtons's third law of motion states that for every action, there is an equal and opposite reaction. This law can be seen in everyday situations, such as when walking on the ground, the force you apply to the ground with your foot causes the ground to push back with an equal force, allowing you to move forward. It also explains the recoil of a gun when fired, as the force of the bullet being pushed forward is matched by the force of the gun moving backward.

5. What is the significance of Newtonian mechanics in modern science?

Newtonian mechanics is the foundation of classical mechanics and has been essential in understanding the motion of objects in the physical world. It has many applications in modern science, including engineering, astronomy, and even biology. Without Newton's laws of motion, we would not have been able to develop technologies such as airplanes, cars, and space travel.

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