Momentum Concepts – Newton’s second law, impulse, force-time graphs, conservation of momentum, elastic & inelastic collisions

Momentum Concepts – Newton’s second law, impulse, force-time graphs, conservation of momentum, elastic & inelastic collisions

To distinguish it from generalized momentum, the product of mass and velocity is also referred to as mechanical, kinetic or kinematic momentum. Momentum is a corner stone concept in Physics. That is, within a closed system of interacting objects, the total momentum of that systemdoes not change value. where is the position vector of the object that describes the object’s position with respect to the reference point.

Inertia is the tendency of an object to stay at rest or in motion. - Acceleration involves a change in velocity and velocity is a vector with a magnitude (15 m/s, 22 m/s, etc.) and a direction (east, northeast, etc.). Accelerating objects are either changing the magnitude of the velocity by speeding up or slowing down or changing the direction of the velocity by turning. True - The weight of an object is equal to the force of gravity acting upon the object. It is computed by multiplying the object's mass by the acceleration of gravity (g) at the given location of the object.

For example, if you were to triple the mass of an object, then the momentum of that object would also triple. And, if you were to change the mass of an object by a factor of 1/2, then the momentum of that object would also change by a factor of 1/2. So if you were to double the velocity of an object, then the momentum of that object would also double. And, if you were to change the velocity of an object by a factor of 1/4, then the momentum of that object would also change by a factor of 1/4.

And similarly, rows 4 and 5 show that a halving of the mass results in a doubling of the acceleration (if force is held constant). Acceleration is inversely proportional to mass. The definition of the standard metric unit of force is stated by the above equation. One Newton is defined as the amount of force required to give a 1-kg mass an acceleration of 1 m/s/s. Unless an unbalanced force acts on an object, an object at rest stays at rest and an object in motion stays in motion.

It can also be generalized to situations where Newton's laws do not hold, for example in the theory of relativity and in electrodynamics. For instance, when a gun is fired, a small mass (the bullet) moves at a high speed in one direction.

Inertia causes an oscillator to go past equilibrium. The motion of an oscillator is the result of an interaction between a restoring force and inertia. For example, the restoring force pulls a pendulum toward equilibrium. But, because of Newton's first law, the pendulum does not just stop at equilibrium. According to the first law, an object in motion tends to stay in motion.

What Is Momentum:

On the moon, 100 grams of flour would make a very big cake, if you measured it with a spring balance. 1 Newton of flour would work just like on earth. The exact details of drawing free-body diagrams are discussed later. For now, the emphasis is upon the fact that a force is a vector quantity that has a direction.

If the location of the object is changed, say from the Earth to the moon, then the acceleration of gravity is changed and so is the weight. It is in this sense that the weight of an object is dependent upon the acceleration of gravity.

Imagine you've gone bowling and a child before you rolled the ball so slowly it stopped mid-lane. No one is around to help you and you don't want to walk out on the lane yourself. You decide to roll your bowling ball into the one stopped on the lane to get it moving. We know that momentum is the quantity of motion of a moving body, but what, exactly, does that mean?

The direction of the momentum vector is the same as the direction of the velocity of the ball. In a previous unit, it was said that the direction of the velocity vector is the same as the direction that an object is moving. If the bowling ball is moving westward, then its momentum can be fully described by saying that it is 10 kg•m/s, westward. As a vector quantity, the momentum of an object is fully described by both magnitude and direction.

For instance, its the tendency of a moving object to keep moving at a constant velocity (or a stationary object to resist changes from its state of rest). False - Inertia (or mass) has nothing to do with gravity or lack of gravity.

• For this graph the impulse (the area under the graph) is 2000 kg ms-1.
• If an object is accelerating to the right, the net force on the object must be directed towards the right.
• That is, momentum is not destroyed in the collision, but transferred between the two objects.
• In this example, the subcontinent is moving as slowly as few inches per year but the mass of the Indian-subcontinent is very high.
• This angle can be in either radians or degrees, as long as you have your calculator in the right mode.
• Inertia is simply the tendency of an objects to resist a change in whatever state of motion that it currently has.

If you did, perhaps you believe in the fatal misconception that a rightward force is required to sustain a rightward motion. The sleds motion to the right can be described as a leftward accelerated motion.

Kinda True (Mostly False) - Weight is the product of mass and the acceleration of gravity (g). To gain weight, one must either increase their mass or increase the acceleration of gravity for the environment where they are located. So the statement is true if one disregards the word MUST which is found in the statement.

Type of Motion

To fully describe the force acting upon an object, you must describe both the magnitude (size or numerical value) and the direction. Thus, 10 Newton is not a full description of the force acting upon an object. In contrast, 10 Newton, downward is a complete description of the force acting upon an object; both the magnitude (10 Newton) and the direction (downward) are given. The principle of conservation of momentum when two objects interact the total momentum remains the same provided no external forces are acting. The big difference between the two types of collisions is that in a perfectly inelastic collision, both the objects are stuck together at the end.

Determine the accelerations that result when a 12-N net force is applied to a 3-kg object and then to a 6-kg object. Furthermore, the qualitative relationship between mass and acceleration can be seen by a comparison of the numerical values in the above table. Observe from rows 2 and 3 that a doubling of the mass results in a halving of the acceleration (if force is held constant).

We use the term momentum in various ways in everyday language, and most of these ways are consistent with its precise scientific definition. We speak of sports teams or politicians gaining and maintaining the momentum to win. We also recognize that momentum has something to do with collisions. For example, looking at the rugby players in the photograph colliding and falling to the ground, we expect their momenta to have great effects in the resulting collisions.

Newton's First Law of Motion states that no force is needed to keep something moving in a straight line at a constant speed. A force is needed to stop that motion or to change it in some way. This is a description of inertia, which is a property of all things.

If an object is moving with a constant speed in a circle, then the forces acting upon the object are balanced. True - The weight of an object depends upon the mass of the object and the acceleration of gravity value for the location where it is at. The acceleration of gravity on the moon is 1/6-th the value of g on Earth.

Conservation of momentum is a mathematical consequence of the homogeneity (shift symmetry) of space (position in space is the canonical conjugate quantity to momentum). That is, conservation of momentum is a consequence of the fact that the laws of physics do not depend on position; this is a special case of Noether's theorem. Momentum is a conserved quantity, meaning that the total initial momentum of a system must be equal to the total final momentum of the system. Momentum is a vector quantity, which has both direction and magnitude. Its unit is kg m/s (kilogram metre per second) or N s (newton second).

A force is a push or pull upon an object resulting from the object's interaction with another object. Whenever there is an interaction between two objects, there is a force upon each of the objects. When the interaction ceases, the two objects no longer experience the force. Forces only exist as a result of an interaction. The area under a force – time graph gives us the impulse of the force applied (and hence the change in momentum of the object).