1.Calculate the momentum of an object if:
(a)its mass is 4.0 kg and its velocity is 8.0 ms-1
(b)its mass is 500 kg and its velocity is 3.0 kms-1
(c)a force of 20 N is applied to it for 6.0 s and it moves from rest (d)its mass is 2.0 kg and it falls from rest for 10 s (assuming g = 10 ms-1 or 10 Nkg-1).

2.A car of 1200 kg is pushed along a level road by two men. If they use a force of 800 N and frictional forces acting against them are 560 N, calculate: (a)the work done by the men they push the car for 10 m (b)the momentum gained by the car if the men push for 10 s.

3.A railway truck traveling along level track at 9 ms-1 collides with, and becomes coupled to, a stationary truck. Find the velocity of the coupled trucks immediately after the collision if the stationary truck has a mass which is: (a)equal to the mass of the moving truck

(b)twice the mass of the moving truck.

4.Two planes of the same mass collide head-on and become tangled so that they move on together. If the engines of both were stopped at the moment of impact and the speeds of the planes at impact were 120 ms-1 and 200 ms-1, find the joint velocity immediately after collision.

5.Two boys of masses 45 kg and 60 kg sit facing one another on light frictionless trolleys holding the ends of a strong taut cord between them. The lighter boy tugs the cord and acquires a velocity of 2 ms-1. What is the initial velocity of the other boy?

6.To make a course correction, a spaceship fires 5 kg of fuel out of its rocket engines as hot gases moving at 10000 ms-1. If the mass of the spacecraft is 20000 kg, calculate its change of velocity. Assume that the mass of the spaceship remains constant.

...MOMENTUM QUESTIONS
1. Which has greater momentum: a train at rest or a moving skateboard? Since the train is not moving, it has zero momentum. The skateboard, as long as it has some speed, will have more momentum, since p = m*v. 2. What are the ways to increase impulse? Impulse depends on the magnitude of the applied external force and the time that the force acts on the system. By increasing either of those, impulse on a system will be increased, and the system’s momentum will change accordingly. 3. For the same force, why does a long rifle impart more speed to a bullet than a short pistol? The long barrel means that the force of the expanding gases from the gunpowder is able to push for more time on the bullet (since the push will continue as long as the bullet is in the barrel). Impulse = (Applied Force)*(time) 4. When you are in the way of a moving object and a collision is sure to occur, are you better off decreasing its momentum over a short time or over a long time? Explain. The amount of force you will feel is the same as the force you apply to the object. So if you decrease its momentum over a long time, less force is needed to act. So, you would be “better off” exerting a small force for a long time. 5. Why is it a good idea to have your hand extended forward when you are getting ready to catch a fast-moving baseball with your bare hand? Having your hand forward...

...Change of momentum is related to the forces acting on the vehicle or the driver. Explain how we can increase the safety of the driver based on the above statement.
Momentum of an object can be defined as the product of the mass of the object and its velocity. The unit of momentum is kgms-1. Momentum is a vector quantity, and it has both magnitude and direction. Its direction is the same as the direction of the object’s velocity.Momentum = mass x velocity
p = m v
Momentum can also be defined as inertia in motion. To have momentum, the object must be moving. Momentum tells how hard it is to get something to stop or to change directions. Every moving object has momentum and any object with momentum is going to be hard to stop. To stop such an object, it is necessary to apply a force against its motion for a given period of time. The more momentum the object has, the harder it is to be stopped. Thus, it would require a greater amount of force or a longer amount of time or both to bring such an object to a halt. Force acting for a given amount of time will change an object's momentum. As the force acts upon the object for a given amount of time, the object's velocity is changed, and hence, the object's momentum is changed.1 If the force acts opposite the object's motion, it slows the object...

...STAGE 2 PHYSICS
Assessment Type 1: Investigation Folio
Practical Investigation 2: Momentum
Purpose:
To investigate the relationship between the laws of conservation of momentum and Newton’s Third Law and another variable of your choice for a 2D collision of two objects.
Materials:
Hover puck
Video Recorder
Tripod
Masking tape
Ruler
Tracker (Computer Program)
Method:
On a flat surface containing no
obstacles, prepare the tripod and
camera over the selected area that
the collision will take place
Align masking tape 45 degrees from each corner as a shown above (the arrows). This can be used as a guide for the person releasing the pucks (Optional step)
Test the camera angle so that it captures the collision and the before and after speeds. Make sure you have enough room for this
Identify and label which puck will be the variable and the one which will be held constant. These pucks must be held constant throughout the entire practical
Have a person ready with the camera, while another aligns the pucks in their initial positions. Once ready, signal the camera person, and record the collision at least 3 times
Repeat collision altering the variable puck in which ever way you have chosen to do. In our case we added 100g of weight each time. Record each change you make and record them at least 3 times each
Analyse the data collected and choose the best video of each variable and begin to import them into...

...
Free Fall
Rachel Shea
Physics 131 Lab, QL
Hasbrouck 210
Sept. 21, 2014
Abstract
This experiment measures the study of motion by observing the force of gravity acting solely upon an object, and also measures reaction time. If an object is in free fall, the only force acting upon it is gravity. The object used in this experiment was a golf ball that provided some acceleration when dropped. A sensor positioned underneath a table recorded the golf ball’s pattern of motion, when dropped. The main objective of performing this experiment is to measure the velocity and position of the ball to eventually find the acceleration of free fall. A computer program called, DataStudio, was used to create a graph of position vs. time and a graph of velocity vs. time. The second part of the experiment involved randomly dropping a ruler and having your partner catch it to determine reaction time.
Questions
1. The parabolic curves open upward instead of downward because of the golf balls movement over time: where it is dropped from, to where it ends up. The ball begins close to the sensor, then drops to the ground, then bounces back up closer to sensor again, therefore the bounces correspond with the bottom curves of the parabola. If the data were collected from the floor then the curve would open downward. But because the sensor graphs the position from the sensor, the curve was upwards.
2.
-4572009207500
The slope of the velocity versus time graph physically...

...What is momentum?
Momentum of a body is defined as the mass multiplied by the velocity of this object.
Momentum= m x v
Momentum and Newton’s second law of motion:
The resultant force is proportional to the change in momentum per a second.
We know that force = mass x acceleration. So F (mv-mu)/t
F m (v-u)/t = ma so F=kma
Momentum is a vector quantity:
Momentum has a direction as well as a magnitude
Momentum and Newton’s first law of motion:
An object remains at rest or in uniform motion unless acted upon by a force.
If an object had a constant momentum, it will have a constant amount of force needed to that will mean that no resultant force acting on it. So it will have a constant velocity unless the mass changes.
Momentum key points
Unit of momentum:
Kgms-1
Symbol of momentum:
P
But what is momentum as a physical quantity?
Momentum is the measure of how much force is needed to stop the moving object or change its velocity (speed or direction)
Momentum is found in lots of examples from our everyday lives. To understand what momentum is we look at two colliding objects. Each object is moving with a certain velocity and has a certain mass. To stop this object a certain force must be applied to counter the...

...AP Physics Summer Assignment with
Dr. Crymes
Welcome to AP Physics B! It is a college level
physics course that is fun, interesting, and challenging
on a level you’ve not yet experienced. This assignment
will review all of the prerequisite knowledge expected of
you. There are 7 parts to this assignment. By taking the
time to review and understand all parts of this
assignment, you will help yourself acclimate to the rigor
and pacing of APPhysics. The summer assignment will
be “due” the first day of class. Good luck!
1. First off: send me your email address to jonathan_crymes@gwinnett.k12.ga.us so that I can make a class
list and hopefully send you some cool stuff over the summer. No extra work, I promise. Preferably
today, but no later than June 30, email me to introduce yourself. Please include the following
information with your email:
- First name, last name, last math class taken and grade received.
- What do you hope to get out of this course besides a good grade?
- Do you have any physics questions you’ve always wondered about like: what is a black hole? Is time
travel really possible? What is “relativity”? or “quantum physics”? or “if the Universe is filled with
stars, why is it dark in space but not on Earth?” or the classic “Did Einstein really fail his math class?”
2. Okay, remember how in chemistry they use symbols like “O” for oxygen and “H” for hydrogen and...

... The PSBB Millennium School Geruhambakkam Chennai
XII PhysicsWorksheet
Electric charges and field
1. 1. An oil drop of 12 excess electrons is held stationary under a constant electric field of 2.55x104 v/m. The density of oil is 1.26 gm/cc. Estimate the radius of the drop.[Ans:1.428x10-6m]
2. Two small spheres each of mass 10-6kg are suspended from a point by silk threads 50 cm long. They are equally charged and repel to a distance of 20cm.Calculate the charge on each.[Ans:3.012x10-9C]
3. Two charges +20µC and -20µC are placed 20cm apart at A and B respectively. Compute the electric field at C 20 cm away from both A and B.[Ans:4.5x106N/C]
4. Calculate the work done in turning a dipole of moment 36x10-6 C m aligned in an electric field of 5X 105 N C-1 through an angle of 180º.[Ans:36J]
5. Two charges +1µC and -1µC are 1 cm apart. Calculate the electric field at a point distant 10 cm from the midpoint (i) on the axial line (ii) on the equatorial line.
6. A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density 80 µC/m2 . Find the charge on the sphere. What is the total electric flux leaving the surface of the sphere?
7. Two point charges +4e and +e are separated by a distance ‘a’. Where should the third point charge be placed for it to be in equilibrium? • 2µC
8. Two equal positive charges each of +2µC and 3m
a charge of+3µC are placed as shown....

...Abstract:
The students investigated about freezing point depression and at what temperature the substance changes states. The students used the freezing point depression to find the molar mass of benzoic acid. First they heated lauric acid to determine the temperature that the freezing point of the solvent is and then compared the temperature to that of the lauric acid/ benzoic acid solution. They then took the change in temperature in order to determine the molality of the benzoic acid, which was calculated to be 1 mol/kg. Then they found the moles of benzoic acid to be 0.00805 mol. using what they found in the experiment they compared it with the 1.00 g of benzoic acid that was added to in experiment, they found that the molar mass of benzoic acid was 125.46 g/mol.
Apparatus:
Materials:
Lauric Acid
Benzoic Acid
Culture Tube With Cap
Safety Goggles
Bunsen Burner
Wire Gauze
Iron Ring
Spatula
Blank Label
Ring Stand
400-mL Beaker
Thermometer
Utility Clamp
Paper Towels
Theory:
The lab focused on molality and its relation to the temperature change of a substances freezing point depression. Students relationship found the equation delta T = K(f) x m. Students were figure out that based on the molar mass of benzoic acid added that it affected the freezing point of lauric acid. The freezing point of the solution is depressed because the molecules of the benzoic acid allowed for the bonding of the lauric acid molecules, therefore increasing the...