• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

According to Newton's first law, an object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Extracts from this document...

Introduction

According to Newton's first law, an object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force. It is the natural tendency of objects to keep on doing what they're doing. All objects resist changes in their state of motion. In the absence of an unbalanced force, an oject in motion will maintain this state of motion. This is often called the law of inertia.

Consider for instance the unfortunate collision of a car with a wall. Upon contact with the wall, an unbalanced force acts upon the car to abruptly decelerate it to rest. Any passengers in the car will also be deccelerated to rest if they are strapped to the car by seat belts. Being strapped tightly to the car, the passengers share the same state of motion as the car. As the car accelerates, the passengers accelerate with it; as the car decelerates, the passengers decelerate with it; and as the car maintains a constant speed, the passengers maintain a constant speed as well.

If the car were to abruptly stop and the seat belts were not being worn, then the passengers in motion would continue in motion.

...read more.

Middle

image01.png

Now consider a book sliding from left to right across a table top. Sometime in the prior history of the book, it may have been given a shove and set in motion from a rest position. Or perhaps it acquired its motion by sliding down an incline from an elevated position. Whatever the case, our focus is not upon the history of the book but rather upon the current situation of a book sliding across a table top. The book is in motion and at the moment there is no one pushing it to the right.

The force of gravity pulling downward and the force of the table pushing upwards on the book are of equal magnitude and opposite directions. These two forces balance each other. Yet there is no force present to balance the force of friction. As the book moves to the right, friction acts to the left to slow the book down. There is an unbalanced force; and as such, the book changes its state of motion. The book is not at equilibrium and subsequently accelerates. Unbalanced forces cause accelerations. In this

...read more.

Conclusion

image05.png

All objects resist changes in their state of motion. All objects have this tendency - they have inertia. But do some objects have more of a tendency to resist changes than others? Absolutely yes! The tendency of an object to resist changes in its state of motion is dependent upon mass. Inertia is that quantity which is exclusively dependent upon mass. The more mass which an object has, the more inertia it has - the more tendency it has to resist changes in its state of motion.

Suppose that there are two seemingly identical bricks at rest on the physics lecture table. Yet one brick consists of mortar and the other brick consists of Styrofoam. Without lifting the bricks, how could you tell which brick was the Styrofoam brick? You could give the bricks an identical push in an effort to change their state of motion. The brick which offers the least resistance is the brick with the least inertia - and therefore the brick with the least mass (i.e., the Styrofoam brick).

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Mechanics & Radioactivity section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Mechanics & Radioactivity essays

  1. Peer reviewed

    Sir Isaac Newton.

    3 star(s)

    The mechanics of the Copernican astronomy of Galileo attracted him and he also studied Kepler's Optics. He recorded his thoughts in a book, which he entitled Quaestiones Quaedam Philosophicae (Certain Philosophical Questions). It is a fascinating account of how Newton's ideas were already forming around 1664.

  2. Centripetal force

    It is because it dips at an angle to the vertical line since the vertical component of the tension () balances the weight of the rubber bung. The force acts towards the centre of the circle is not equal to the tension T.

  1. Free essay

    CIRCULAR MOTION - revision notes and calculations

    From these 3 equations: ? R1 = m/2(g - V2h/ra) R2 = m/2(g + V2/ra) Note: (1) R2 never vanishes since it always has a positive value, but if V2 = arg/h (i.e. g = V2h/ra), R1 = 0. That means the car is about to overturn outwards.

  2. Centripetal motion. The objective of this experiment is to verify whether the tension ...

    It was very formidable for the rubber bung to swirl in a purely horizontal plane. Even if it could, during the 30 revolutions, the motion of the rubber bung might alter and not be swirled in a horizontal plane for some revolutions.

  1. Centripetal Force

    force must be increased so that it can move with the same angular velocity before. This can be done by adding more weights to the system. 3.5 How does the centripetal force required for circular motion depend on the angular velocity and the radius of the orbit?

  2. Investigating the Inverse Square Law

    d0)2 should produce a straight-line graph, passing through the origin, if the inverse square law is followed. Source: 'A Laboratory Manual of Physics' -F. Tyler, Page 269 The gradient of the line obtained is a measure of the strength of the source used in the experiment.12 The strength of the source is the activity, A=?N.

  1. Investigating how height affects time taken for a falling object to reach ground level.

    Obtaining Evidence: Height (cm) Time taken for ball to reach ground (seconds) Mean Result Mean Result2 1st 2nd 3rd 4th 5th 100 0.456 0.454 0.458 0.454 0.454 0.455 0.207 90 0.432 0.431 0.431 0.432 0.432 0.432 0.186 80 0.406 0.407 0.406 0.407 0.406 0.406 0.165 70 0.380 0.382 0.382

  2. Charles's Law

    Question: How did the did the volume- temperature data obtained by Charles lead to the concept of absolute zero? Answer: Charles saw a linear relationship between the volume and temperature of a gas. Extrapolating backwards, he found that the point where a gas would have no volume would be -273 degrees Celsius.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work