Motion, Strobe and Newton's Laws

AI Thread Summary
Motion at constant velocity means that an object maintains a steady speed and direction, while motion at constant acceleration involves a change in velocity over time. The distinction lies in the fact that constant velocity has zero acceleration, whereas constant acceleration indicates that velocity is changing. When comparing the strobe effects of a baseball and a lead ball falling from the same height with negligible drag, both will display the same strobe pattern, as all objects fall at the same acceleration regardless of weight. The scenario of a package sliding in a pickup truck illustrates Newton's first law, as the package's motion is affected by the truck's acceleration and the frictional force acting on it. Understanding these concepts clarifies the principles of motion and Newton's laws.
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I have some questions that I need help answering and are due friday september 30th but i need the help to answer them. ok here goes. The question is What is the difference between motion at constant velocity and motion at constant acceleration? Explain your answer.
I say that there is no difference because motion at constant velocity and constant acceleration is zero. Is that right or is there someway you can help me understand.
The other question is if you have a baseball and a lead ball, that is much heavier, that is falling from the same height as the baseball, and the drag is negligible how would the strobe of the lead be different from the baseball strobe?
My answer to this was they would be the same. Our teacher said something about the weight has nothing to do with it. I am confused because I missed that day of lecture due to a sick kid. can you help me understand?
Another question was if a package is placed in a bed of a pickup truck and it slides towards the back when speeding up and towards the front when slowing down. Which Newtons law? apply it directly to the motion and explain why.
I think it is Newtons first law but the laws confuse me. I need help explaining the laws to answer this question.
 
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physicsidiot71784 said:
I have some questions that I need help answering and are due friday september 30th but i need the help to answer them. ok here goes. The question is What is the difference between motion at constant velocity and motion at constant acceleration? Explain your answer.
I say that there is no difference because motion at constant velocity and constant acceleration is zero. Is that right or is there someway you can help me understand.
I am not sure what you mean by your answer. Motion at constant velocity (eg. 100 m/sec) is zero?

With constant (non-zero) acceleration, the velocity is continually changing. So if you measure the velocity at different times you will get different velocities. With constant velocity (0 acceleration) the velocity is the same at all times.

The other question is if you have a baseball and a lead ball, that is much heavier, that is falling from the same height as the baseball, and the drag is negligible how would the strobe of the lead be different from the baseball strobe?
My answer to this was they would be the same. Our teacher said something about the weight has nothing to do with it. I am confused because I missed that day of lecture due to a sick kid. can you help me understand?
This is just Galileo's 'time of fall' experiment. All objects fall with the same acceleration (g).
Another question was if a package is placed in a bed of a pickup truck and it slides towards the back when speeding up and towards the front when slowing down. Which Newtons law? apply it directly to the motion and explain why.
I think it is Newtons first law but the laws confuse me. I need help explaining the laws to answer this question.
It demonstrates Newton's first and second laws. The package is not attached to the truck. It is held on the bed by friction. If the truck engine applies force to the truck, the truck accelerates. But the package on the bed can only accelerate at the same rate if the force which the truck is exerting on the package (friction) is sufficient to accelerate the package at the same rate. Otherwise it maintains uniform motion (and the truck accelerates under it).

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