As we have said, momentum is a vector quantity. Since momentum is a vector, the techniques of vector addition discussed in Chapter
[link] must be used to calculate the total momentum of a system.
Two billiard balls roll towards each other. They each have a mass of 0,3 kg. Ball 1 is moving at
to the right, while ball 2 is moving at
to the left. Calculate the total momentum of the system.
The question
explicitly gives
the mass of each ball,
the velocity of ball 1,
, and
the velocity of ball 2,
,
all in the correct units!
We are asked to calculate the
total momentum of
the system . In this example our system consists of two balls. To find
the total momentum we must determine the momentum of each ball and add them.
Since ball 1 is moving to the right, its momentum is in this direction,
while the second ball's momentum is directed towards the left.
Thus, we are required to find the sum of two vectors acting along the
same straight line. The algebraic method of vector addition introduced
in Chapter
[link] can thus be used.
Let us choose right as the
positive direction, then obviously left is negative.
The total momentum of the system is then the sum of the two momenta taking the
directions of the velocities into account. Ball 1 is travellingat 1 m
s
to the right or +1 m
s
. Ball 2 is travelling at 0,8 m
s
to the left or -0,8 m
s
. Thus,
In the last step the direction was added in words. Since the result
in the second last line is positive, the total momentum of the systemis in the positive direction (i.e. to the right).
Exercise
The fastest recorded delivery for a cricket ball is 161,3 km
hr
, bowled by Shoaib Akhtar of Pakistan during a match against England in the 2003 Cricket World Cup, held in South Africa. Calculate the ball's momentum if it has a mass of 160 g.
The fastest tennis service by a man is 246,2 km
hr
by Andy Roddick of the United States of America during a match in London in 2004. Calculate the ball's momentum if it has a mass of 58 g.
The fastest server in the women's game is Venus Williams of the United States of America, who recorded a serve of 205 km
hr
during a match in Switzerland in 1998. Calculate the ball's momentum if it has a mass of 58 g.
If you had a choice of facing Shoaib, Andy or Venus and didn't want to get hurt, who would you choose based on the momentum of each ball.
Two golf balls roll towards each other. They each have a mass of 100 g. Ball 1 is moving at
= 2,4 m
s
to the right, while ball 2 is moving at
= 3 m
s
to the left. Calculate the total momentum of the system.
Two motor cycles are involved in a head on collision. Motorcycle A has a mass of 200 kg and was travelling at 120 km
hr
south. Motor cycle B has a mass of 250 kg and was travelling north at 100 km
hr
. A and B are about to collide. Calculate the momentum of the system before the collision takes place.
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
