A stationary trolley of mass 1.0kg is free to move along a frictionless horizontal surface. For the first 10s, a steady horizontal force of 0.5N is applied to the trolly.
What is the speed of the trolley after 10s?
I know the answer, which is 5m/s, but WHY will the trolly continue to move even after 10s when no force is acting on it anymore? Please explain! Thanks!
What is the speed of the trolley after 10s?
I know the answer, which is 5m/s, but WHY will the trolly continue to move even after 10s when no force is acting on it anymore? Please explain! Thanks!
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Newton's first law:
Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.
If the trolly has a velocity of 5m/s and no force applied to it, it will continue to move in 5m/s.
In the real world, the trolly would be subject to friction from the surface as well as air resistance, and it would eventually stop. In an ideal model like the one you're calculating, those factors have been eliminated from the equation.
Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.
If the trolly has a velocity of 5m/s and no force applied to it, it will continue to move in 5m/s.
In the real world, the trolly would be subject to friction from the surface as well as air resistance, and it would eventually stop. In an ideal model like the one you're calculating, those factors have been eliminated from the equation.
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As the other users have stated it's due to Newton's 1st Law which states: Every object will remain in its state of rest or uniform motion in a straight line unless a net external force acts on it.
In this case, the force is applied and the trolley is free to move on a frictionless, horizontal surface. Thus you can ignore friction and being horizontal the gravitational pull will have no effect.
As such, it will continue to move in lieu of any dissipative forces or external force that will cause it to stop.
In this case, the force is applied and the trolley is free to move on a frictionless, horizontal surface. Thus you can ignore friction and being horizontal the gravitational pull will have no effect.
As such, it will continue to move in lieu of any dissipative forces or external force that will cause it to stop.
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Let me refer you to Newton's 1st law of motion
'A body will remain at rest, or , if moving, will move in a straight line, UNLESS ACTED ON BY AN EXTERNAL FORCE.'
If the trolley is on a frictionless surface and if we ignore air resistance, then, when the driving force is removed, it will just continue to go on its merry way until some OTHER force brings it to a stop, or changes its direction.
Old Newt knew his stuff!!
'A body will remain at rest, or , if moving, will move in a straight line, UNLESS ACTED ON BY AN EXTERNAL FORCE.'
If the trolley is on a frictionless surface and if we ignore air resistance, then, when the driving force is removed, it will just continue to go on its merry way until some OTHER force brings it to a stop, or changes its direction.
Old Newt knew his stuff!!
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Netwon's first (?) law: every body continues in straight motion until an external force is applied to it.