Momentum science physics presentation reporting

Science momentum

1. GROUP 2 MOMENTUM

2. INDEX Linear momentum Examples of momentum Momentum and Newton’s seconds law Mathematical analysis of momentum and newton’s second law. Law of conservation of momentum Examples Quiz

3. LINEAR MOMENTUM Momentum is directly proportional to the object’s mass and also its velocity. Thus the greater an object’s mass or the greater its velocity, the greater its momentum. Momentum P is a vector having the same direction as the velocity v. The SI unit for momentum is kg·m /s and can also be expressed as Ns Linear Momentum: Linear momentum is defined as the product of a system’s mass multiplied by its velocity. In symbols, linear momentum is expressed as P =  mv .

4. Examples of Momentum: 1.A semi-truck full of logs has a large mass and must slow down long before a stop light because even with a small velocity, it has a large momentum and is difficult to stop. 2.A four-wheeler moving at a relatively fast velocity has a smaller momentum than the semi-truck because of its small mass and will stop much faster. 3.A bullet, although small in mass, has a large momentum because of an extremely large velocity.

5. Momentum and Newton’s Second Law   Momentum was deemed so important that it was called the “quantity of motion.” Newton actually stated his second law of motion in terms of momentum: The net external force equals the change in momentum of a system divided by the time over which it changes. Using symbols, this law is F​ net ​​=​ Δp /​​ Δt ,where F net is the net external force, Δp is the change in momentum, and Δt  is the change in time. ( when a net force acts on a body, it produces acceleration in the direction of the net force. The magnitude of this acceleration is directly proportional to the net force acting on the body and inversely proportional to its mass)

6. Newton’s second law and linear momentum (mathematical analysis) According to the Newton’s second law of motion, F=ma (1) Since acceleration a is defined as the rate of change of velocity, a=∆v/ ∆t (2) Put equation (2) in equation (1) F=m ∆v/ ∆t By rearranging the above equation we get, F= ∆( mv )/ ∆t (3) Now, as we know that, P= mv (4) We put equation (1) in equation (3) F= ∆p/ ∆t Or F= P2-P1/t2-t1

7. Law of conservation of momentum The law of conservation of momentum states that for two objects colliding in an isolated system, the total momentum before and after the collision is equal (remains constant). This is because the momentum lost by one object is equal to the momentum gained by the other .Conservation of momentum is derived from Newton's laws of motion. Newton's third law states that every action has an equal but opposite reaction; the force that one object A exerts on object B is equal but opposite to the force that object B exerts on object A. By Newton's second law, this force is equal to the product of the mass and the acceleration of the objects, so the product of the mass and acceleration of object A is equal but opposite to the product between the mass and acceleration of object B.

8. True or False Momentum is inversely proportional to the object’s mass and velocity TRUE FALSE Momentum is a vector quantity TRUE FALSE Momentum can be represented by the symbol ‘m’ TRUE FALSE 4. Einstein stated the second law in terms of momentum TRUE FALSE Net force is the total external force applied on a body TRUE FALSE The momentum lost by one object is equal to the momentum gained by the other TRUE FALSE To every action there is an equal but reverse reaction TRUE FALSE

9. MCQs The units for momentum are a. kg b. m/s c. kg-m/s d. kg/m/s 2. The formula for momentum is a. mass divided by velocity b. mass multiplied by velocity c. velocity divided by mass d. Force times acceleration 3. The law of conservation of momentum states that,  a. p before is less than p after b. p before is the same as p after c. p before is more than p after

10. 4. The difference between a car hitting a wall vs. a car hitting a hay stack is a. the Impulse on the car hitting the wall is greater b. the change in momentum of the car hitting the wall is greater c. the force on the car hitting the hay stack is greater d. the collision time of the car hitting the hay stack is greater 5. A 0.250 kg cart moving at 0.400 m/s has how much momentum? a. 0.1 kg-m/s b. 1 kg-m/s c. 10 kg-m/s d. 100 kg-m/s

11. Answer the following Questions What is meant by linear momentum? Ans : Linear momentum is defined as the product of a system’s mass multiplied by its velocity. Give an example of law of conservation of momentum? Ans : A system of gun and a bullet .Before firing the gun, both the gun and the bullet are at rest ,so the total momentum of the system is Zero .As the gun is fired, bullet shoots out of the gun and acquires momentum .To conserve momentum of the system ,the gun recoils .According to the law of conservation of momentum ,the total momentum of the gun and the bullet will be zero after the gun is fired.

12. What is the Newton's second law of motion? Ans : when a net force acts on a body, it produces acceleration in the direction of the net force. The magnitude of this acceleration is directly propotional to the net force acting on the body and inversely propotional to its mass mathematically: F=ma What is the SI unit of momentum? Ans : The SI unit for momentum is kg · m/s and can also be expressed as Ns