where:
is the mass of object 1 (kg)
is the mass of object 2 (kg)
is the initial velocity of object 1 (m
s
+ direction)
is the initial velocity of object 2 (m
s
- direction)
is the final velocity of object 1 (m
s
- direction)
is the final velocity of object 2 (m
s
+ direction)
This equation is always true - momentum is always conserved in collisions.
A toy car of mass 1 kg moves westwards with a speed of 2 m
s
. It collides head-on with a toy train. The train has a mass of 1,5 kg and is moving at a speed of 1,5 m
s
eastwards. If the car rebounds at 2,05 m
s
, calculate the velocity of the train.
We will choose to the east as positive.
A helicopter flies at a speed of 275 m
s
. The pilot fires a missile forward out of a gun barrel at a speed of 700 m
s
. The respective masses of the helicopter and the missile are 5000 kg and 50 kg. Calculate the new speed of the helicopter immmediately after the missile had been fired.
helicopter and missile
= 5000 kg
= 50 kg
=
= 275 m
s
= ?
= 700 m
s
The helicopter and missile are connected initially and move at the same velocity. We will therefore combine their masses and change the momentum equation as follows:
Note that speed is asked and not velocity, therefore no direction is included in the answer.
A bullet of mass 50 g travelling horizontally at 500 m
s
strikes a stationary wooden block of mass 2 kg resting on a smooth horizontal surface. The bullet goes through the block and comes out on the other side at 200 m
s
. Calculate the speed of the block after the bullet has come out the other side.
We will choose to the right as positive.
Physics in action: impulse
A very important application of impulse is improving safety and reducing injuries. In many cases, an object needs to be brought to rest from a certain initial velocity. This means there is a certain specified change in momentum. If the time during which the momentum changes can be increased then the force that must be applied will be less and so it will cause less damage. This is the principle behind arrestor beds for trucks, airbags, and bending your knees when you jump off a chair and land on the ground.
Questions & Answers
I'm interested in biological psychology and cognitive psychology
Communication is effective because it allows individuals to share ideas, thoughts, and information with others.
effective communication can lead to improved outcomes in various settings, including personal relationships, business environments, and educational settings. By communicating effectively, individuals can negotiate effectively, solve problems collaboratively, and work towards common goals.
it starts up serve and return practice/assessments.it helps find voice talking therapy also assessments through relaxed conversation.
miss
Every time someone flushes a toilet in the apartment building, the person begins to jumb back automatically after hearing the flush, before the water temperature changes. Identify the types of learning, if it is classical conditioning identify the NS, UCS, CS and CR. If it is operant conditioning, identify the type of consequence positive reinforcement, negative reinforcement or punishment
nature is an hereditary factor while nurture is an environmental factor which constitute an individual personality. so if an individual's parent has a deviant behavior and was also brought up in an deviant environment, observation of the behavior and the inborn trait we make the individual deviant.
Samuel
I am taking this course because I am hoping that I could somehow learn more about my chosen field of interest and due to the fact that being a PsyD really ignites my passion as an individual the more I hope to learn about developing and literally explore the complexity of my critical thinking skills