Impulse and Momentum Objectives. 1. Define momentum. 2
... 2. Distinguish between elastic and inelastic collisions.
3. Use conservation principles to solve problems involving elastic and inelatic collisions for
initial velocity, final velocity or mass, given the other values.
4. Define impulse; distinguish between impulse and force.
5. Determine the impulse ...
... We can also test the motion of a rocket under vertical ascent numerically, as done in this website (Choose #3
from the physlets.), from Evelyn Patterson at the US Air Force Academy. Try an initial mass of fuel of 20000kg,
and see what happens.
LECTURE 7: , PAGES 58-71, these notes, SECTION 3.1 (Ret ...
... applied to a 5kg object vs. the time the force is
applied. Find the final velocity of the object if the
original velocity was 12m/s.
Momentum and Impulse - Oakland Schools Moodle
... Momentum is a vector quantity
• To fully describe the momentum of a 5-kg
bowling ball moving westward at 2 m/s,
you must include information about both
the magnitude and the direction of the
• p = 5 kg * 2 m/s west
• p = 10 kg * m / s west
332 Unit 7 Momentum student handout
• Jack and Leon are fishing in their boat when they
decide to jump into the water. Jack, 45-kg, jumps off
the front of the boat with a speed of 2m/s. While at
the exact same moment, Leon, 90-kg, jumps out of the
back of the boat at a speed of 4m/s.
If the boat has a mass of 100 kg and was a ...
Solutions to Unit Conversion Practice Problems
... Perform the following unit manipulations.
a. A jet engine provides a thrust (force) of 2,000 lbf with a velocity of 600 km/hr.
What is the power produced in horsepower?
Power = Force x Velocity
Convert to SI
Force = 2000 (lbf) x 4.448 (N/lbf) = 8896 N
Velocity = 600 (km/hr) x 0.278 [(m/s)/( ...
PHYSICS 211, Exam # 3 April 22, 2013 (Dr. Xinhua Bai`s session
... 2. Two objects interact with each other and with no other objects. Initially object A has a speed
of 5 m/s and object B has a speed of 10 m/s. In the course of their motion they return to their
initial positions. Then A has a speed of 4 m/s and B has a speed of 7 m/s. We can conclude:
A) the potenti ...
Specific impulse (usually abbreviated Isp) is a measure of the efficiency of rocket and jet engines. By definition, it is the impulse delivered per unit of propellant consumed, and is dimensionally equivalent to the thrust generated per unit propellant flow rate. If mass (kilogram or slug) is used as the unit of propellant, then specific impulse has units of velocity. If weight (newton or pound) is used instead, then specific impulse has units of time (seconds). The conversion constant between these two versions is the standard gravitational acceleration constant (g0). The higher the specific impulse, the lower the propellant flow rate required for a given thrust, and in the case of a rocket, the less propellant needed for a given delta-v, per the Tsiolkovsky rocket equation.Specific impulse is a useful value to compare engines, much like miles per gallon or liters per 100 kilometers is used for cars. A propulsion method and system with a higher specific impulse is more propellant-efficient. While the unit of seconds can seem confusing to laypeople, it is fairly simple to understand as ""hover-time"": how long a rocket can ""hover"" before running out of fuel, given the weight of that propellant/fuel. Of course, the weight of the rocket has to be taken out of consideration and so does the reduction in fuel weight as it's expended; the basic idea is ""how long can any given amount of x hold itself up"". Obviously that must mean ""...against Earth's gravity"", which means nothing in non-Earth conditions; hence Isp being given in velocity when propellant is measured in mass rather than weight, and the question becomes ""how fast can any given amount of x accelerate itself?""Note that Isp describes efficiency in terms of amount of propellant, and does not include the engine, structure or power source. Higher Isp means less propellant needed to impart a given momentum. Some systems with very high Isp (cf. ion thrusters) may have relatively very heavy/massive power generators, and produce thrust over a long period; thus, while they are ""efficient"" in terms of propellant mass carried, they may actually be quite poor at delivering high thrust as compared to ""less efficient"" engine/propellant designs.Another number that measures the same thing, usually used for air breathing jet engines, is specific fuel consumption. Specific fuel consumption is inversely proportional to specific impulse and the effective exhaust velocity. The actual exhaust velocity is the average speed of the exhaust jet, which includes fuel combustion products, nitrogen, and argon, as it leaves air breathing engine. The effective exhaust velocity is the exhaust velocity that the combusted fuel and atmospheric oxygen only would need to produce the same thrust. The two are identical for an ideal rocket working in vacuum, but are radically different for an air-breathing jet engine that obtains extra thrust by accelerating the non-combustible components of the air. Specific impulse and effective exhaust velocity are proportional.