Friday

May 6, 2016
Number of results: 45,910

**math**

The head of an industrial machine moves in a straight line horizontally backwards and forwards from a central position. The movement can be modelled using the sine wave d = 80 sin ( pie t), where d is the horizontal distance (in cm) from the central starting position, and t is...
*May 3, 2007 by clara*

**Physics **

Two 1kg blocks rest on opposite sides of the double inclined plane. One inclined planes makes an angle of 30 degrees and the other an angle of 60 degrees with horizontal. The masses are connected by a light cord passing over a friction less pulley. What is the largest value of...
*October 5, 2015 by Nicholle*

**phys**

a 5 kg concrete block accelerates down a 34 degree slope at 4.2m/s^2. Find the coefficient of friction between the block and the slope. The net force along the slope that produces the acceleration is F = M g sin 34 - u M g cos 34 = M a where u is the coefficient of friction. M...
*June 19, 2006 by slien*

**Physics**

What is the kinetic energy in MeV of a π–meson that lives 1.80×10-16 s as measured in the laboratory, and 0.840×10-16 s when at rest relative to an observer, given that its rest energy is 135 MeV?
*November 16, 2014 by Ashton*

**physics**

What is the kinetic energy in MeV of a π–meson that lives 1.80×10-16 s as measured in the laboratory, and 0.840×10-16 s when at rest relative to an observer, given that its rest energy is 135 MeV?
*November 16, 2014 by Tim*

**physics**

1 A block of mass mb sits atop a at wooden plank of mass mp on a plane inclined an angle theta with respect to thehorizontal. The two are supported near the bottom of the plane by a spring of spring constant k that is in contactwith the plank but not the block. If the coecient...
*October 18, 2011 by lala*

**Physics **

A mass M is initially at rest on a horizontal surface, μs=0.30 and μk=0.20 . A horizontal string then pulls M with a tension T. N is the normal component of the contact force. All quantities below are magnitudes. Answers are either true or false. 1)The total force on...
*June 18, 2013 by Cori Smith*

**Physics**

An object begins at rest on a frictionless inclined plane at a linear distance of 2.0m from the base of the incline. If the incline makes an angle of 20 degrees with the horizontal, determine the time it will take for the object to reach the base of the incline.
*February 10, 2014 by Tim*

**Physics**

A car starts rolling down a l-in-4 hill (l-in-4 means that for each 4 m traveled along the road, the elevation change is 1 m). How fast is it going when it reaches the bottom after traveling 55 m? (a) Ignore friction, (b) Assume an effective coefficient of friction equal to 0....
*November 3, 2013 by Jill*

**Physics**

A spaceship approaches Starbase Beta with an initial velocity moving in the +x direction. The ensign sets the ship’s computer to initiate a braking program starting at time t = 0. After this time the computer controls the ship’s x-velocity according to until the ship docks at ...
*September 19, 2009 by Sonya*

**chemistry (work shown)**

How would you make a serial dilution if you have a starting value 100mM of X The are the values of X show different dilutions. Volume variables (x) mL 0 1 3 1 10 30 100 We starting out with 100mM of X which would be considered its concentration. In order to describe how to do ...
*January 28, 2007 by tatiana*

**math**

11. Runner A crosses the starting line of a marathon and runs at an average pace of 5.6 miles per hour. Half an hour later, Runner B crosses the starting line and runs at an average rate of 6.4 miles per hour. If the length of the marathon is 26.2 miles, which runner will ...
*April 7, 2010 by Anonymous*

**physics**

A horizontal force of magnitude F = 110 N is used to push a box of mass m = 6 kg from rest a distance d = 16 m up a frictionless incline with a slope q = 28°. a) How much work is done by the force on the box? b) How much work is done on the box by the gravitational force ...
*February 26, 2011 by Lyla*

**physics**

a car starts from rest and attains a velocity of meter/sec,then acceleration changes and it aquires the velocity of 20meter/sec in next 5sec .then it slows down and comes to rest in next 5sec.draw a velocity-time graph for the given conditions,and find acceleration of 3 given ...
*May 4, 2016 by kiran*

**physics**

Two blocks, joined by a string, have masses of 6 and 9kg. They rest on frictionless horizontal surface. A 2nd string, attached only to the 9kg block, has a horizontal force = 30N applied to it. Both blocks accelerate. Find the tension in the string between the blocks.
*October 19, 2008 by Tiffany*

**physics**

At t = 0 a block with mass M = 5 kg moves with a velocity v = 2 m/s at position xo = -.33 m from the equilibrium position of the spring. The block is attached to a massless spring of spring constant k = 61.2 N/m and slides on a frictionless surface. At what time will the block...
*December 1, 2014 by stewart*

**Physics**

A dockworker applies a constant horizontal force of 90.0Nto a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves a distance 12.0min a time of 5.20s.If the worker stops pushing after 5.20s, how far does the block ...
*October 5, 2012 by Karina*

**Physics**

A box accidentally falls from the back of a truck and hits the ground with a speed of 15m/s. It slides along the ground for a distance of 45 m before coming to rest. Determine a) the length of time the box slides before stopping c) the time it takes to slide the last 10 m.
*October 28, 2007 by Alex*

**physics**

A 9-kg block is held by a pulley system shown in fig. What force must the person exert in the following cases: a) to hold the block at rest. b) to lower it at 2m/s. c) to raise it with an acceleration of 0.5 m/s2? Ignore the mass of small pulley. Answer Thi
*March 22, 2016 by Anonymous*

**Algebra**

Using a graph, solve for x and y below. If 6x - 3y = 24 & 18x + 3y = 12 I know to use the forumla y = m*x + b. I also know to assume x=0 so that your starting point is (0,b) with b representing the y axis. M represents slope, which is rise over run. What I am having trouble ...
*June 20, 2015 by Jamie*

**physics**

A roller coaster moves 85 m horizontally, then travels 45 m at an angle of 30.0 degrees above the horizontally. what is the displacement from its starting point? use graphical techniques. horizontal: 85 + 45 cos 30 = ? vertical: 45 sin 30 = ?
*December 25, 2006 by yostina*

**Math/ Proportions solve using unit rates**

Contestants in a dance-a-thon rest for the same amount of time every hour. A couple rests for 25 minutes in 5 hours. How long did they rest in 8 hours? 25/5=5 8/5= 1 3/8 hours
*November 11, 2015 by Dee*

**Physics**

Suppose a hockey puck slides down a frictionless ramp with an acceleration of 4.70 m/s2. What angle does the ramp make with respect to the horizontal? Please show steps...
*February 6, 2014 by Ray*

**Physics**

A dockworker applies a constant horizontal force of 82.0 to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves a distance 12.5 in a time 4.60 .
*January 12, 2012 by Michael*

**Physics**

A proton is released from rest inside a region of constant, uniform electric field E1 pointing due North. 14.8 seconds after it is released, the electric field instantaneously changes to a constant, uniform electric field E2 pointing due South. 8.07 seconds after the field ...
*January 23, 2016 by Joe*

**science**

An electron had a constant acceleration of +3.2m/s^2. At a certain instant its velocity is +9.6m/s. What is its velocity at a)2.5 s earlier and b )2.5s later? I will be happy to critique your work. I could a= change in velocity / change in time ? Here's the question: "An ...
*September 10, 2006 by Sarah*

**Physics**

A 4.5 g dart is fired into a block of wood with a mass of 23.8 g. The wood block is initially at rest on a 1.3 m tall post. After the collision, the wood block and dart land 3.6 m from the base of the post. Find the initial speed of the dart.
*February 16, 2011 by Steve*

**Momentum**

A 4.4 g bullet is fired into a block of wood with a mass of 21.3 g. The wood block is initially at rest on a 1.3 m tall post. After the collision, the wood block and bullet land 2.4 m from the base of the post. Find the initial speed of the bullet.
*May 16, 2012 by Lui*

**Physics**

A 4.3 g dart is fired into a block of wood with a mass of 22.6 g. The wood block is initially at rest on a 1.4 m tall post. After the collision, the wood block and dart land 3.1 m from the base of the post. Find the initial speed of the dart.
*October 24, 2012 by Angela*

**Physics**

A 4.3 g dart is fired into a block of wood with a mass of 22.6 g. The wood block is initially at rest on a 1.4 m tall post. After the collision, the wood block and dart land 3.1 m from the base of the post. Find the initial speed of the dart.
*October 24, 2012 by Angela*

**Physics**

A 3.5 g dart is fired into a block of wood with a mass of 22.8 g. The wood block is initially at rest on a 1.3 m tall post. After the collision, the wood block and dart land 2.6 m from the base of the post. Find the initial speed of the dart. m/s
*October 29, 2014 by Anonymous*

**Physics**

A 4.1 g dart is fired into a block of wood with a mass of 20.2 g. The wood block is initially at rest on a 1.2 m tall post. After the collision, the wood block and dart land 2.6 m from the base of the post. Find the initial speed of the dart.
*February 28, 2015 by Betty*

**Physics**

A 37 kg child roller skates, initially at rest, rolls 2.0 m down an incline at an angle of 17 degrees with the horizontal. If there's no friction, what is the kinetic energy of the child at the bottom of the incline?
*February 3, 2011 by Ash*

**Physics**

A 37 kg child roller skates, initially at rest, rolls 2.0 m down an incline at an angle of 17 degrees with the horizontal. If there's no friction, what is the kinetic energy of the child at the bottom of the incline?
*February 3, 2011 by Ash*

**Physics**

A 37 kg child roller skates, initially at rest, rolls 2.0 m down an incline at an angle of 17 degrees with the horizontal. If there's no friction, what is the kinetic energy of the child at the bottom of the incline?
*February 3, 2011 by Ash*

**Physics**

A spring with k=40.0 N/m is at the base of a frictionless 30.0 degree inclined plane. A 0.50-kg object is pressed against the spring, compressing it 0.20m from its equilibrium position. The object is then released. If the object is not attatched to the spring, how far up the ...
*March 26, 2011 by Work needed!*

**Physics**

A spring with k=40.0 N/m is at the base of a frictionless 30.0 degree inclined plane. A 0.50-kg object is pressed against the spring, compressing it 0.20m from its equilibrium position. The object is then released. If the object is not attatched to the spring, how far up the ...
*March 27, 2011 by Anonymous*

**physics**

Block 1, of mass1 = 0.550kg , is connected over an ideal (massless and frictionless) pulley to block 2, of mass2 , as shown. For an angle of = 30.0 and a coefficient of kinetic friction between block 2 and the plane of = 0.300mu(kinetic friction), an acceleration of magnitude...
*October 23, 2012 by Samantha*

**Physics**

Block 1, of mass m1 = 0.650kg , is connected over an ideal (massless and frictionless) pulley to block 2, of mass m2, as shown. For an angle of θ = 30.0∘ and a coefficient of kinetic friction between block 2 and the plane of μ = 0.400, an acceleration of ...
*October 3, 2013 by Joe*

**Finance**

My uncle Samuel has $450,000 invested at 6.5%, and he plans to retire. He wants to withdraw $40,000 at the beginning of each year, starting immediately. How many years will it take to exhaust her funds, run the account down to zero?
*November 4, 2013 by granann*

**physics- please help**

World-class sprinters can accelerate out of the starting blocks with an acceleration that is nearly horizontal and has magnitude 15m/s^2 . Part a)How much horizontal force F must a sprinter of mass 60kg exert on the starting blocks to produce this acceleration? express your ...
*April 29, 2012 by Emma*

**physics**

A skier starts from rest at the top of a frictionless incline of height 20.0 m, as shown in the figure. At the bottom of the incline, the skier encounters a horizontal surface where the coefficient of kinetic friction between skis and snow is 0.208. Neglect air resistance.Find...
*March 6, 2015 by josef*

**Physics**

If the block slides down the incline at a constant speed, what is the force of friction between the block and the plane?
*January 22, 2012 by Katherinee*

**Algebra 2**

Which of the following methods can be used to construct a pattern of 10 numbers for which it would be mathematically impossible to predict the 11th term? (more then one answer.) A.Make a pattern, starting with 3, where each number is the next digit of pi (3.14159 . . .). B....
*April 4, 2013 by Tifini*

**Algebra**

Which of the following methods can be used to construct a pattern of 10 numbers for which it would be mathematically impossible to predict the 11th term? (more then one answer.) A.Make a pattern, starting with 3, where each number is the next digit of pi (3.14159 . . .). B....
*April 4, 2013 by Help Please!*

**physics**

A ball starts from rest and accelerates at 0.520 m/s2 while moving down an inclined plane 9.65 m long. When it reaches the bottom, the ball rolls up another plane, where, after moving 14.40 m, it comes to rest. (a) What is the speed of the ball at the bottom of the first plane...
*October 10, 2009 by Jamie*

**physics**

You are skiing and have a mass of 47 kg and are on a slope making an angle of 37 degrees above horizontal. The coefficient of kinetic friction between the skis and the snow is 0.18. What is the amount of force pulling you down the slope? What is your acceleration down the slope?
*February 22, 2015 by Anna*

**physical**

A bullet of mass 0.01 kg is moving horizontally with a speed of 100 m/s when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 0.4. After the collision the bullet becomes embedded in the block.
*January 26, 2012 by dhaval*

**Physics**

A small block of mass m = 194 g is released from rest at point A , along the horizontal diameter on the inside of a hemispherical bowl of radius R = 29.5 cm, and the surface of the bowl is rough. The block's speed at point B is 1.56 m/s.
*October 2, 2013 by Leticia*

**Algebra**

Teri finds a pile of money with at least $600. If she puts $200 of the pile in her left pocket, gives away 4/5 of the rest of the pile, and then puts the rest in her right pocket, she'll have more money than if she instead gave away $600 of the original pile and kept the rest...
*February 7, 2015 by Jason*

**math**

Directions: Find the slope of any line perpendicular to the line through points(0,5) and (-3,-4). THis is what i did. m=(-4-5)/(-3-0)=(9)/(3)=3 y=mx+b using points :(0,5) 5=3(0)+b 5=b y=3x+5 so the slope of the perpendicular line is (-1)/(3) When finding the slope, you got ...
*January 24, 2007 by Jasmine20*

**Physics**

A 50kg skier starts from rest from the top of a 100m slope. What is the speed of hte skier on reaching the bottom of the slope? Neglect friction. would i do this: =PE + KE =mgh +1/2mv^2 =50(10)(100) + 1/2 (50)v^2 =50000 +25v^2 =2000 =v^2 44.7m/s =v Is this correct? Thank in ...
*October 16, 2007 by Andrea*

**Physics**

If you were in a smooth-riding train with no windows, could you sense the difference between uniform motion and rest? Between accelerated motion and rest? How could you make such a distinction with a bowl filled with water?
*April 30, 2008 by Tiffany*

**Physics**

solve physics question. a train moves 3.6km from rest to rest in 3minutes. the greatest speed is 90km/h, and the acceleration and retardation are uniform. find the distance travelled at full speed.
*June 17, 2013 by Anonymous*

**phy**

Three blocks are suspended at rest by the system of strings and frictionless pulleys shown in the figure below, where W = 29.0 N, and è = 26.6°. What are the weights w1 and w2?
*October 25, 2012 by anthony*

**physics**

Three blocks are suspended at rest by the system of strings and frictionless pulleys shown in the figure below, where W = 29.0 . What are the weights w1 and w2?
*October 25, 2012 by anthony*

**nova**

7) You throw a 12-N stone vertically into the air from ground level. You observe that when it is 15.0 m above the ground, it is traveling at 25.0 m/s upward. Use the work –energy theorem to find (a) the stone’s speed just as it left the ground and (b) its maximum height. 8) A ...
*September 20, 2014 by papy*

**Physics 2**

A 10 g bullet is fired into, and embeds itself in, a 2 kg block attached to a spring with a force constant of 19.6 n/m and whose mass is negligible. How far is the spring compressed if the bullet has a speed of 300 m/s just before it strikes the block and the block slides on a...
*January 20, 2012 by Dee*

**Physics**

A 1000-kg car is driving toward the north along a straight road at a speed of 20.0 m/s. The driver applies the brakes and the car comes to a rest in a distance of 140 m. What is the constant force applied to the car to bring it to rest?
*November 1, 2011 by Christine*

**physics(URGENT!!!!!)**

A block of mass m=2 kg on a horizontal surface is connected to a spring connected to a wall (see figure). The spring has a spring constant k= 12 N/m. The static friction coefficient between the block and the surface is μs= 0.6 , and the kinetic friction coefficient is &#...
*November 3, 2013 by Anonimus*

**PHYSICS**

A block of mass'm'is dropped over a horizontal surface with an initial velocity'v'.the coefficient of kinatic friction is'u'(mev),while the acceleration due to gravity'g'before coming to rest the block travels a distance??how i can find the distance?please help me to do so!
*April 26, 2012 by M.sani*

**physics**

A 20 kg mass is allowed to accelerate down a frictionless 15° ramp. a. Determine the value of the x-component of the force gravity. b. What is the acceleration of the block down the ramp. c. How long will it take for the block to slide 30.0m?
*January 18, 2012 by Anonymous*

**physics**

Two blocks are connected by a string over a frictionless, massless pulley such that one is resting on an inclined plane and the other is hanging over the top edge of the plane. the hanging block has a mass of 16 kg and the one on the plane has a mass of 8 kg. the coefficient ...
*January 18, 2010 by emm*

**physics**

A 500 g steel block rotates on a steel table while attached to a 2.0-m-long massless rod. Compressed air fed through the rod is ejected from a Inozzle on the back of the block, exerting a thrust force of 3.5 N. The nozzle is 70^\circ from the radial line, as shown in the ...
*November 10, 2010 by Kathleen*

**physics**

After flying for 15 min in a wind blowing 42 km/h at an angle of 20° south of east, an airplane pilot is over a town that is 42 km due north of the starting point. What is the speed of the airplane relative to the air?
*September 17, 2009 by Nick*

**physics**

After flying for 15 min in a wind blowing 42 km/h at an angle of 20° south of east, an airplane pilot is over a town that is 42 km due north of the starting point. What is the speed of the airplane relative to the air?
*September 17, 2009 by Nick*

**physics**

After flying for 15 min in a wind blowing 42 km/h at an angle of 20° south of east, an airplane pilot is over a town that is 42 km due north of the starting point. What is the speed of the airplane relative to the air?
*September 17, 2009 by Nick*

**Physics**

After flying for 15 min in a wind blowing 42 km/h at an angle of 34° south of east, an airplane pilot is over a town that is 40 km due north of the starting point. What is the speed of the airplane relative to the air?
*July 10, 2010 by Sam*

**physics**

After flying for 13 min in a wind blowing 37 km/h at an angle of 25° south of east, an airplane pilot is over a town that is 59 km due north of the starting point. What is the speed of the airplane relative to the air, in km/h?
*September 2, 2011 by Pat Rick*

**Physics**

After flying for 15 min in a wind blowing 42 km/h at an angle of 28° south of east, an airplane pilot is over a town that is 42 km due north of the starting point. What is the speed of the airplane relative to the air?
*February 5, 2013 by Patricia*

**physics**

After flying for 13 min in a wind blowing 44 km/h at an angle of 21° south of east, an airplane pilot is over a town that is 53 km due north of the starting point. What is the speed of the airplane relative to the air?
*September 9, 2015 by Help*

**physics**

A cannon fires a shell at an angle of 20º to the horizontal. The shell reaches a range of 436 meters, landing at the same elevation as the starting point. What was the initial velocity of the shell
*October 22, 2011 by Anonymous*

**mit**

Quiz 12, Problem 4 (2 points possible) A uniform rod of length d is initially at rest on a flat, frictionless table. The rod is pivoted about a point a distance d/3 from one of its ends, and is free to rotate on the table about this pivot. A small glob of clay (mass m) ...
*March 23, 2016 by juanpro*

**physics**

A bullet with mass m = 5.21 g is moving horizontally with a speed v=367 m/s when it strikes a block of hardened steel with mass M = 14.8 kg(initially at rest). The bullet bounces o the block in a perfectly elastic collision. (a) What is the speed (m/s) of the block immediately...
*December 15, 2011 by Sarah*

**Physics **

3.2 kg block is given an initial velocity of 12 m/s across horizontal surface. after travels 8 m speed is 2.4 m/s. determine coefficient of friction bewern block and surface and how far it travels before coming to rest
*November 3, 2014 by Anonymous *

**Physics**

A small block slides along a track from one level to a higher level, by moving through an intermediate valley (see Figure). The track is frictionless until the block reaches the higher level. There a frictional force stops the block in a distance d. Assume that the block's ...
*December 26, 2013 by George*

**physics**

The system shown below consists of a block of mass M = 4.4 kg resting on a frictionless horizontal ledge. This block is attached to a string that passes over a pulley, and the other end of the string is attached to a hanging block of mass m = 1.9 kg. The pulley is a uniform ...
*March 16, 2012 by Nick*

**Physics**

A 5.0-g bullet traveling horizontally at an unknown speed hits and embeds itself in a 0.195-kg block resting on a frictionless table. The block slides into and compresses a 180-N/m spring a distance of 0.15m before stopping the block and bullet. Determine the initial speed of ...
*March 11, 2014 by BULTURP*

**Physics**

(b) Given that Icm = ½MR2 for a uniform solid wheel, (i) show that the rotational kinetic energy is half the translational kinetic energy for such a wheel. (ii) For the wheel of diameter 10 cm, find its final speed after traversing a distance of 10 m down an incline of 25º. ...
*July 20, 2010 by Oisin*

**Physics**

A 1000kg car is driving toward the north along a straight horizontal road at a speed of 20.0 m/s. The driver applies the brakes and the car comes to a rest uniformly in a distance of 150 m. What is the magnitude applied to the car to bring it to rest?
*March 12, 2016 by Anonymous*

**physics**

A lumberjack (mass = 98 kg) is standing at rest on one end of a floating log (mass = 270 kg) that is also at rest. The lumberjack runs to the other end of the log, attaining a velocity of +2.6 m/s relative to the shore, and then hops onto an identical floating log that is ...
*January 12, 2015 by Anonymous*

**math**

In a tank, there is 100 liter of water before starting the taps. If each tap fills 25 liters per houIn a tank, there is 100 liter of water before starting the taps. If each tap fills 25 liters per hour and 5 taps continue to fill 4 hours and 4 taps for only 15 minuted each....
*April 19, 2016 by ramzan*

**Physics**

3. Johnny, of mass 65 kg, and Lucy, of mass 45 kg, are facing each other on roller blades. The coefficient of kinetic friction between the roller blades and concrete surface is 0.20. When Johnny pushes Lucy from rest he applies a force for 1.0 s. Lucy then slows down to a stop...
*June 17, 2015 by Furkan*

**Physics**

A young woman named Kathy Kool buys a sports car that can accelerate at the rate of 4.6 m/s2. She decides to test the car by dragging with another speedster, Stan Speedy. Both start from rest, but experienced Stan leaves the starting line 0.8 s before Kathy. If Stan moves with...
*March 28, 2012 by Dave*

**bobpursley**

ok im doing my physics homework and we have to submit the answers online. i keep getting these questions wrong and i only have one more try can someone please tell me how to work it? a 2.5 kg otter starts from rest at the top of a muddy incline 94.6 cm long and slides down to ...
*October 15, 2008 by Claudia*

**physics**

12.5 kg wooden crate with an initial velocity of 2.5 m/s slides across a rough cement floor for 1.7 m before coming to rest. Calculate the coefficient of kinetic friction
*October 29, 2012 by Anonymous*

**Physics**

A gun is fired vertically into a 1.60 kg block of wood at rest directly above it. If the bullet has a mass of 21.0 g and a speed of 195 m/s, how high will the block rise into the air after the bullet becomes embedded in it?
*January 20, 2016 by Jeff*

**Physics **

An 8.0g bullet is fired into a 2.5 Kg block at rest at the edge of a friction-less table of height 1.0 m. The bullet remains in the block and after the impact the block lands (d) distance from the bottom of the table. Find the initial speed of the bullet. Now I do realize this...
*December 15, 2015 by Aziz*

**physics**

A 0.150 block moving vertically upward collides with a light vertical spring and compresses it 4.50 before coming to rest. If the spring constant is 54.0 , what was the initial speed of the block? (Ignore energy losses to sound and other factors during the collision.)
*December 17, 2009 by Ramon*

**urgent physics ?**

I have drawn my force body diagrams, but I need help making forming the equation for this problem. Any assistance is greatly appreciated! A 60 kg block slides along the top of a 100 kg block. The lighter block has an acceleration of 3.8 m/s2 when a horizontal force F= 390 N is...
*October 3, 2014 by stevie*

**relativity **

A particle called neutral pi meson (or pion) decays into two photons (and nothing else).If the pion (whose rest mass is 135Mev) is initially at rest, What are the energies of the photons? How are they moving with respect to each other ?
*June 7, 2011 by walter *

**Maths B**

Abbey steers her boat in a North Easterly direction for 15 s, East for 6 s and then stops to avoid hitting a duck. If her boat travels at a constant speed of 10 m/min during this time, what is the distance and compass bearing of Abbey’s boat from the starting point when it ...
*April 2, 2012 by Rianna*

**physics**

A block of wood of mass 6.0 kg slides along a skating rink at 12.5 m/s^2 [w] . The block slides onto a rough section of ice that exerts a force of 30 N force of friction on the block of wood. The acceleration of the block of wood is 5.0 m/s^2 [E] and it takes 2.5s to stop. How...
*March 27, 2012 by Isabella*

**physics**

A block of wood of mass 6.0 kg slides along a skating rink at 12.5 m/s^2 [w] . The block slides onto a rough section of ice that exerts a force of 30 N force of friction on the block of wood. The acceleration of the block of wood is 5.0 m/s^2 [E] and it takes 2.5s to stop. How...
*March 27, 2012 by Isabella*

**Maths**

Runner A speed 1km/hour Runner B speed 2km/hour They start of at the same point at the oval.In a lap that is 500m, how many times will they meet at the starting point after 10 hours. I managed to get the LCM for runner A,B using the time taken to complete 1 lap A=1/2 hrs, B=1/...
*February 11, 2015 by Sandy*

**physics**

A person pushes with force F on a box which remains at rest on a rough floor as shown in the top figure. The bottom figures illustrates all the force acting on the box. a) What condition must be satisfied by all the force acting on the box so that it remains at rest? Draw a ...
*April 5, 2013 by /*

**physical**

an orienteer runs 300m north and then 400m to the southeast (at a 45 degree angle to north). if he runs at a constant speed, how far away is he from the starting position?
*January 24, 2015 by tarkan*

**physics **

an orienteer runs 300m north and then 400m to the southeast (at a 45 degree angle to north). if he runs at a constant speed, how far away is he from the starting position?
*January 24, 2015 by tarkan*

**physics**

consider a solid cylinder rolling from rest down a plane inclined at an angle theta to the horizontal.After rolling down a distance s down the plane,determine (i) acceleration of the cylinder (ii) if the cylinder is hollow ; find its acceleration after a distance s
*August 3, 2011 by victor2*

**Physics**

A 23.0 kg block is initially at rest on a horizontal surface. A horizontal force of 80.0 N is required to set the block in motion. After it is in motion, a horizontal force of 57.0 N is required to keep the block moving with constant speed. Find the coefficients of static and ...
*November 2, 2010 by Maria*