Physics
Unit 1 Lab 2
Unit 1 Lab 2 Laws of Motion Lab
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Student Name: |
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If you were late or missed lab, give the reason below: |
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Review:
Newton’s First Law: If the Net Force on an object is zero, it will not accelerate.
If an object is at rest, it will remain at rest. If an object is in motion, it will move with constant velocity, that is, at constant speed in a straight line.
Newton’s Second Law: If the Net Force on an object is not zero, it will accelerate in the direction of the net force.
Equations of Motion
Velocity includes direction indicator, usually a + or – sign.
Part 1 Newton’s 1st and 2nd Law of Motion
Open PhET Simulation Forces and Motion, Basics (see Canvas).
Link: https://phet.colorado.edu/sims/html/forces-and-motion-basics/latest/forces-and-motion-basics_en.html
Select the 4th window labeled Acceleration twice.
Leave Friction setting at the default position.
Check all the boxes.
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Using the arrow keys gradually apply a force to the right on the crate and determine the maximum force that can be applied without overcoming the force of static friction to start the crate moving. Once the crate starts moving, pause the simulation. |
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What was maximum force of static friction? |
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What was the force of kinetic friction once the crate starts moving? |
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What applied force got the crate moving? (this should the the current applied force setting)? |
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What is the net force on the crate? |
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What is the acceleration of the crate? |
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Show that this demonstrates . |
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Remember to provide units for all numbers and use a negative sign to indicate vector quantities that point left.
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Reduce the force until the net force (labeled “sum of forces” in the simulation) equals zero. |
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What is the acceleration of the crate now? |
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These tests should verify important aspects of Newtons’ 1st and 2nd Laws of Motion.
Part 2 Gravity
Open the simulation. See Canvas for the link.
https://phet.colorado.edu/sims/html/gravity-force-lab-basics/latest/gravity-force-lab-basics_en.html
How does the force exerted by the small mass on the large mass compare to the force exerted by the large mass on the small mass?
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Put an X in the left next to the correct answer. |
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The small mass exerts less force on the large mass than the large mass exerts on the small. |
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b |
The small mass exerts the same force on the large mass as the large mass exerts on the small. |
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The small mass exerts more force on the large mass than the large mass exerts on the small. |
This is due to
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Put an X in the left next to the correct answer. |
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Newton’s First Law of Motion |
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Newton’s Second Law of Motion |
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Newton’s Third Law of Motion |
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d |
Conservation of momentum |
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e |
Conservation of energy |
Set each mass in the simulation to whatever mass you like and position the masses at a distance of your choice, provided the masses are not identical to each other and provided your values are not identical to anyone else’s.
Record your values in the table and record the force of gravity according to the simulation.
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Mass 1 |
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Mass 2 |
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Distance |
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Convert distance to standard units |
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Force of mass 1 on mass 2 |
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Force of mass 2 on mass 1 |
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If the direction of the force is to the left, indicate this by making the force negative.
Use the formula for the force of gravity to confirm this number:
Note: the formula only gives the magnitude of the force, not the direction.
Do the calculation on the eCalc Scientific Calculator (if available) and use a Snipping App to copy and paste an image of the calculation below. The calculator can be found online at this link: https://www.eeweb.com/tools/calculator.
For numbers in scientific notation, use the EE key and enter the exponent without using the multiplication operation or raising 10 to a power. For example, to enter the value for G above, key 6 … decimal point … 6 7 EE (-) 11. The entry line will read 6.67e-11.
Paste image here.
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