Read physics chapter 'Forces and laws of motion’, carefully and prepare any one
small activity related to Newton's first law, 2nd law or 3rd law of motion. (including Aim, Materials required, Procedure, Observation,
Conclusion, Precautions)
Answers
Newton's first law
Ball Bounce Experiment
Materials for the Ball Bounce Experiment:
A basketball or soccer ball, or similar bouncy ball
a smaller bouncy ball (like a tennis ball or a racquet ball).
Have an assortment of other balls handy for further experimenting.
Procedure:
Do this experiment outside
First bounce the basketball and tennis ball side by side to compare their bounces. Start them off around chest height
Make a hypothesis (a guess) about what will happen when you stack the small ball on top of the bigger one and then drop it
Try it! It may take a couple tries to line them up just right but the results are pretty awesome
Explanation:
Perked- Up Playdate 7/20 800x400
The energy of motion from the bigger ball is transferred into the smaller one. Most of your attention is on the sky-rocketing smaller ball, but if you look at the basketball, it doesn’t have much bounce at all!
NEWTON'S SECOND LAW
Apparatus and Materials
Light gate, interface and computer
Dynamics trolley
Pulley and string
Slotted masses, 400 g
Mass, 1 g
Clamp
Ruler
Double segment black card
Pass a piece of string with a mass hanging on one end over a pulley. Attach the other end to the trolley so that, when the mass is released, it causes the trolley to accelerate. Choose a length of string such that the mass does not touch the ground until the trolley nearly reaches the pulley. Fix a 1 kg mass on the trolley with Blu-tack to make the total mass (trolley plus mass) of about 2 kg . This produces an acceleration which is not too aggressive when the maximum force (4 N) is applied.
The force is conveniently increased in 1 newton steps when slotted masses of 100 g are added. Place the unused slotted masses on the trolley. Transfer them to the slotted mass holder each time the accelerating force is increased. This ensures that the total mass experiencing acceleration remains constant throughout the experiment.
Fit a double segment black card on to the trolley. Clamp the light gate at a height which allows both segments of the card to interrupt the light beam when the trolley passes through the gate. Measure the width of each segment with a ruler, and enter the values into the software.
Connect the light gate via an interface to a computer running data-logging software. The program should be configured to obtain measurements of acceleration derived from the double interruptions of the light beam by the card.
The internal calculation within the program involves using the interruption times for the two segments to obtain two velocities. The difference between these, divided by the time between them, yields the acceleration.
A series of results is accumulated in a table. This should also include a column for the manual entry of values for force in newtons. It is informative to display successive measurements on a simple bar chart.
Procedure
Data collection:
Select the falling mass to be 100 g. Pull the trolley back so that the mass is raised to just below the pulley. Position the light gate so that it will detect the motion of the trolley soon after it has started moving.
Set the software to record data, then release the trolley. Observe the measurement for the acceleration of the trolley.
Repeat this measurement from the same starting position for the trolley several times. Enter from the keyboard '1' (1 newton) in the force column of the table (see below).
Transfer 100 g from the trolley to the slotted mass, to increase it to 200 g. Release the trolley from the same starting point as before. Repeat this several times. Enter '2' (2 newtons) in the force column of the table.
Repeat the above procedure for slotted masses of 300 g and 400 g.
Analysis
Depending upon the software, the results may be displayed on a bar chart as the experiment proceeds. Note the relative increase in values of acceleration as the slotted mass is increased.
The relationship between acceleration and applied force is investigated more precisely by plotting an XY graph of these two quantities. (Y axis: acceleration; X axis: force.) Use a curve-matching tool to identify the algebraic form of the relationship. This is usually of the form 'acceleration is proportional to the applied force'.
This relationship is indicative of Newton's second law of motion.
Newton's third law
Take your STEMists outdoors to observe Newton’s 3rd law in action! Watch a bird as it takes flight. Consider the flying motion of the bird and use of its wings as they push the air downwards. The downward motion reacts to the opposite force of the air pushing the bird upwards. This makes perfect sense if your STEMists can remember that for every action, there is an equal (in size) and opposite (in direction) reaction – therefore, the action-reaction force makes it possible for the bird to fly.