Hi, I had some questions about Physics and Newton’s Three Laws of Motion and was wondering if someone could possibly help me. Some of the questions I wasn’t sure about the answers.
#1 Write out in words what “acceleration ~ net force” means.
My Answer: I think it means that acceleration is directly proportional to net force.
#2 True or False: On Earth the mass and weight of an object are the same.
My answer: False
#3 In space, would an object with a weight of 20 Newtons or an object with a mass of 2 kilograms have more Inertia?
My Answer: They would have the same inertia or
The object with a mass of 2 kilograms (I wasn’t sure.)
#4 True or False: For the same net force on an object, less mass means more acceleration.
My Answer: False
#5 True or False: The quantity 1/10 is less than the quantity 1/100. WHY?
My Answer: False, both quantities are the same?! (I was really confused by this question.)
#6 True or False: All free-falling objects have the same force/mass ratio and undergo the same acceleration at the same location.
My Answer: False
Thank you guys so much. I have a huge test over this next week and I still don’t think I’ve grasped the whole idea behind all of these concepts. Physics isn’t my best subject and if anyone knows any good websites that can help me out, I would really appreciate it.
Thank You So much Again -Hannah-
A sled is dragged along a horizontal path at a constant speed of 1.5m/s by a rope that is inclined at an angle of 30 degrees with respect to horizontal. The total weight of the sled is 470N. The tension in the rope is 240N. How much work is done by the rope on the sled in a time interval of 10.0S?
Hi Hannah! I'd be happy to help you out with your questions about Physics and Newton's Three Laws of Motion.
#1 "Acceleration ~ net force" means that acceleration is directly proportional to net force. This means that when the net force acting on an object increases, the acceleration of the object will also increase. They have a linear relationship, so if you double the net force, the acceleration will also double.
#2 You are correct, the statement "On Earth, the mass and weight of an object are the same" is false. Mass and weight are different quantities. Mass is a measure of the amount of matter in an object, while weight is the force with which an object is attracted towards the center of the Earth (or any other gravitational body). Weight depends on both mass and the acceleration due to gravity.
#3 In space, an object with a weight of 20 Newtons and an object with a mass of 2 kilograms would have the same inertia. Inertia is the resistance of an object to changes in its motion, and it depends only on mass. So, regardless of the presence or absence of gravity, objects with the same mass will have the same inertia.
#4 The statement "For the same net force on an object, less mass means more acceleration" is actually true. According to Newton's second law of motion, the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. So, when the mass decreases, the acceleration increases for the same net force.
#5 The quantity 1/10 is indeed less than the quantity 1/100. When you have a fraction, the smaller the number in the denominator, the larger the overall value of the fraction. So, 1/10 is larger than 1/100. You can think of it as breaking a whole into smaller parts - the more parts you have, the smaller each individual part is.
#6 The statement "All free-falling objects have the same force/mass ratio and undergo the same acceleration at the same location" is true. In the absence of any other forces (like air resistance), all objects near the surface of the Earth fall with the same constant acceleration, known as the acceleration due to gravity. This value is approximately 9.8 m/s^2. Since the gravitational force depends on mass (F = mg), the force/mass ratio is the same for all objects, and they all undergo the same acceleration.
If you need additional resources to help you with your Physics studies, I recommend checking out Khan Academy and Physics Classroom. Both websites provide easy-to-understand explanations and practice problems that can enhance your understanding of the subject.
Good luck with your test! Feel free to ask if you have any more questions.