momentum-impulse Science 9 quarter 4.pptx

momentum - impulse

1. MODULE 3 IMPULSE AND MOMENTUM

2. Momentum is defined as the product of mass and the velocity. Its value depends on mass and velocity of the moving object. MOMENTUM p=mv , Where : p =momentum m = mass (kg) v = velocity (m/s) Example: 1. A 325 kg motorcycle is moving at 140 m / s , south. Compute the following: a. momentum b. at what velocity is the momentum of 1754 kg car equal to the motorcycle

3. Given: m (motorcycle) =325kg v (motorcycle)=140 m/s Required : a. p (motorcycle) =? b. v (car) =? p = mv p = (325kg) (140 m/s) = 45, 500 kg.m /s m=1754 kg p = 45500 kg.km/h v = p/m = 45500kg.m/s 1754 kg v =25.94 m/s

4. Remember this: Equation to use If you are looking for…. If you know p=mv momentum Mass and velocity m = p/v mass Momentum & velocity V= p/m velocity Momentum and mass Given Problems : A bowling ball whose mass is 4.0kg is rolling at a velocity of 2.5m/s. What is its momentum? Given: m = 4.0kg v = 2.5 m/s p = mv P = (4.0 kg) (2.5 m/s) p = 10 kg.m /s

5. 2. A skateboard is rolling at a velocity of 3.0 m/s with a momentum of 6.0 kg.m /s. What is its mass? Given: v = 3.0 m/s p = 6.0 kg.m /s m = p/v m = 6.0 kg.m /s 3.0 m/s m = 2.0 kg 3. A pitcher throws a baseball with a mass of 0.5 kg and a momentum of 10 kg.m /s. What is its velocity? Given: m = 0.5 kg p = 10 kg.m /s v = p/m v = 10 kg.m /s 0.5 kg v = 20 m/s

6. IMPULSE Impulse is a force when multiplied by the duration (time) applied to the object. It requires a force to change the momentum of an object. I = Ft Where: I = impulse (N.s) F = force (N= kg.m /s2) t = time (s) According to the second law of motion, where: ∆v = change of velocity (final velocity-initial velocity) ∆v = Vf - Vi F = ma (Force is equal to the product of mass and acceleration) F = m ∆v/t F = m ( vf – vi)/t a = ∆v/t

7. By rearrangement: Ft = mVf – mVi Since: p=mv Ft = pf – pi Ft = Δ p I = Δp Impulse could also be equal to the change in momentum Example 1: A force of 50N is applied to a boulder for 3s. What is the impulse? Given: F= 50 N t= 3 seconds Required: Impulse Required: I ; where I = Ft I = (50N) (3s) = 150 Ns

8. MULTIPLE CHOICE: ½ cw Read each item carefully. Choose letter and words that corresponds to the correct answer. 1. The momentum of any object is calculated by ______. A. Dividing mass by velocity B. Multiplying mass by velocity C. Multiplying mass by acceleration D. Dividing force by acceleration 2. Which object has the greatest momentum? A. An 18-wheeler tractor at rest B. An average mass persons walking C. A sports car driving so fast on a high way D. A baseball thrown by a professional pitcher. 3. Find the momentum of a 23.1 g bullet fired at 621 m/s. A. 14.3 kg.m /s B. 26.9 kg.m /s C. 2.69 x 10² kg.m /s D. 1.43 x 10² kg.m /s

9. 4. An impulse is equivalent to _______. A. The change in mass of an object. B. The change in volume of an object. C. The original momentum of an object. D. A force applied to an object for a period of time. 5. A 27.2 g arrow is fired with a velocity of 87.3 m/s from a bow with a mass of 2.45 kg. Find the impulse on the arrow. A. 2.37 kg.m /s B. 214 kg.m /s C. 3.11 kg.m /s D. 11.3 kg.m /s 6. The change in momentum is 1.52 Ns for a ball that strikes the floor for 1.05 x 10ˉ²s. Find the force applied to the ball. A. 1.60 x 10ˉ² N B. 1.45 x 10² N C. 1.60 N D. 23.8 N

10. 7. According to the conservation of momentum, the momentum before a collision should be ______momentum after a collision. A. twice the original momentum of the object B. greater than C. the same 8. If two bowling balls were to collide head on, and bounce off one another, the collision would be considered a(n) ______collision. 9. Two ice skaters are initially at rest. The 78.2 kg male ice skater pushes his 48.5 kg female partner forward and away from his body with a velocity of 8.46 m/s. What is the male skater’s velocity as a result of the push? A. inelastic B. angular C. explosive D. elastic C. 0.191 m/s backward B. 5.25 m/s backward A. 5.25 m/s forward D. less than D. 13.6 m/s backward

11. 10. Collisions would be inelastic thus damaging each other, In riding a vehicle, how do you prevent damage and save lives? A. Drive slowly but with no seat belt. B. Drive slowly but surely with seatbelt. C. Drive as fast as you could with no seatbelts. D. Drive while you are under the influence of liquor.

12. MULTIPLE CHOICE: ½ cw Read each item carefully. Choose letter and words that corresponds to the correct answer. 1. The momentum of any object is calculated by ______. A. Dividing mass by velocity B. Multiplying mass by velocity C. Multiplying mass by acceleration D. Dividing force by acceleration 2. Which object has the greatest momentum? A. An 18-wheeler tractor at rest B. An average mass persons walking C. A sports car driving so fast on a highway D. A baseball thrown by a professional pitcher. 3. Find the momentum of a 23.1 g bullet fired at 621 m/s. A. 14.3 kg.m /s B. 26.9 kg.m /s C. 2.69 x 10² kg.m /s D. 1.43 x 10² kg.m /s

13. 4. An impulse is equivalent to _______. A. The change in mass of an object. B. The change in volume of an object. C. The original momentum of an object. D. A force applied to an object for a period of time. 5. A 27.2 g arrow is fired with a velocity of 87.3 m/s from a bow with a mass of 2.45 kg. Find the impulse on the arrow. A. 2.37 kg.m /s B. 214 kg.m /s C. 3.11 kg.m /s D. 11.3 kg.m /s 6. The change in momentum is 1.52 N/s for a ball that strikes the floor for 1.05 x 10ˉ²s. Find the force applied to the ball. A. 1.60 x 10ˉ² N B. 1.45 x 10² N C. 1.60 N D. 23.8 N

14. 7. According to the conservation of momentum, the momentum before a collision should be ______momentum after a collision. A. twice the original momentum of the object B. greater than C. the same 8. If two bowling balls were to collide head on, and bounce off one another, the collision would be considered a(n) ______collision. 9. Two ice skaters are initially at rest. The 78.2 kg male ice skater pushes his 48.5 kg female partner forward and away from his body with a velocity of 8.46 m/s. What is the male skater’s velocity as a result of the push? A. inelastic B. angular C. explosive D. elastic C. 0.191 m/s backward B. 5.25 m/s backward A. 5.25 m/s forward D. less than D. 13.6 m/s backward

15. 10. Collisions would be inelastic thus damaging each other, In riding a vehicle, how do you prevent damage and save lives? A. Drive slowly but with no seat belt. B. Drive slowly but surely with seatbelt. C. Drive as fast as you could with no seatbelts. D. Drive while you are under the influence of liquor.