Tuesday

December 1, 2015
**Physics**

The filament in an incandescent light bulb is made from tungsten (resistivity 5.6 x 10-8 Ù·m). The light bulb is plugged into a 120-V outlet and draws a current of 2.36 A. If the radius of the tungsten wire is 0.00464 mm, how long must the wire be? restivity of ...
*Monday, October 12, 2015 by james check please*

**Physics**

Identical +2.83 μC charges are fixed to adjacent corners of a square. What charge (magnitude and algebraic sign) should be fixed to one of the empty corners, so that the total potential at the remaining empty corner is 0 V? φ =k•q/r φ1+ φ2 + φ3 =0...
*Monday, October 12, 2015 by james*

**Ap physics **

A ball rolls down an incline with an acceleration of 10 cm/s^2. If it starts with an initial velocity of 0 cm/s and has a velocy of 50 cm/s when it reaches the bottom of the ramp, how long is the ramp?
*Sunday, October 11, 2015 by Jasmine *

**physics**

A dart leaves the barrel of a blowgun at a speed v. The length of the blowgun barrel is L. Assume that the acceleration of the dart in the barrel is uniform. If the darts exit speed is 17 m/s and the length of the blowgun is 1.10 m, find the time the dart is in the barrel.
*Sunday, October 11, 2015 by nancy*

**Physics **

An Earth satellite moves in a circular orbit 765 km above the Earth's surface. The period of the motion is 99.9 min. (a) What is the speed of the satellite? ______ m/s (b) What is the magnitude of the centripetal acceleration of the satellite? ______m/s^2
*Sunday, October 11, 2015 by Corey*

**physics**

A ball is projected upward at time t = 0 s, from a point on a flat roof 10 m above the ground. The ball rises and then falls with insignificant air resistance, missing the roof, and strikes the ground. The initial velocity of the ball is Consider all quantities as positive in ...
*Sunday, October 11, 2015 by jose *

**Physics**

When the Sun is directly overhead, a hawk dives toward the ground at a speed of 2.18 m/s. If the direction of his motion is at an angle of 25.1◦below the horizontal, calculate the speed of his shadow along the ground. Answer in units of m/s
*Sunday, October 11, 2015 by Natasha*

**Physics**

A factory worker pushes a 32.0 kg crate a distance of 4.9 m along a level floor at constant velocity by pushing downward at an angle of 32 ∘ below the horizontal. The coefficient of kinetic friction between the crate and floor is 0.25. What magnitude of force must the ...
*Sunday, October 11, 2015 by octavio*

**physics**

"A 3.5 kg monket is suspended motionless 35 meter above the ground by holding two vines (a vertical vine and a diagonal vine)" We need to find the tension force in the diagonal vine as well as the angle of the diagonal vine with respect to the y axis. I'm having ...
*Sunday, October 11, 2015 by ana*

**Physics**

An explorer is stranded in the desert. A rescue service has located him using GPS, but can reach him only by plane. A supply package is kicked out the door of the plane while while it is flying at a speed of 61.7 m/s at an altitude of 35 m. Does the package fall straight down?
*Sunday, October 11, 2015 by Lindsey*

**physics**

The problem propmpts us with the info: "Two friends play with a card-board box on a grassy hill side. The boy in the box has a mass of 50.0 kg and the box has a mass of 5.00 kg. The incline of the hill is 44° and its height is 10 meter. Assume that friction plays a ...
*Sunday, October 11, 2015 by ana*

**physics**

A person takes a trip, driving with a constant speed of 93.5 km/h except for a 21.0 min rest stop. If the person's average speed is 69.8 km/h, how much time is spent on the trip and how far does the person travel?
*Sunday, October 11, 2015 by Emma *

**Physics**

A rocket has put your spacecraft in a circular orbit around Earth at an altitude of 350 km. Calculate the force due to gravitational between the Earth and the spacecraft in N if the mass of the spacecraft is 2450 kg.
*Sunday, October 11, 2015 by Kay*

**Physics**

A knight sits on a castle wall during a siege. To while away the time, he notes that boul- ders catapulted from below land on the top of his wall with a vertical velocity of 8.3 m/s. If he is 41 m above the catapult, what is the initial velocity of the boulders? The ...
*Sunday, October 11, 2015 by Chanelle*

**Physics**

A box has a weight of 120 N and is being pulled across a horizontal floor by a force that has a magnitude of 100 N. The pulling force can point horizontally, or it can point above the horizontal at an angle θ. When the pulling force points horizontally, the kinetic ...
*Sunday, October 11, 2015 by Erne*

**physics**

The driver of a car wishes to pass a truck that is traveling at a constant speed of 19.0 m/s . Initially, the car is also traveling at a speed 19.0 m/s and its front bumper is a distance 24.3 m behind the truck's rear bumper. The car begins accelerating at a constant ...
*Sunday, October 11, 2015 by elif*

**Physics**

A simple pendulum has a bob of mass M. The bob is on a light string of length l. The string is fixed at C. At position A, the string if horizontal and the bob is at rest. The bob is released from A and swings to B, where the string is vertical. The tension in the string when ...
*Sunday, October 11, 2015 by Kyle*

**Physics**

A 45 kg girl is sitting on one end of a see-saw, 0.6 m away from the the pivot pt. How far away form the pivot pt must a 60 kg boy sit on the other side in order for the see saw o be balanced?
*Sunday, October 11, 2015 by Hannah*

**Physics**

a uniform meter stick is at rotational equilibrium when 220 g is suspended at 5 com, 120 g is suspended at 90, and the support stand is placed at the 40 cm mark what is the mass of the meter stick?
*Sunday, October 11, 2015 by Hannah*

**physics help**

The distance between the midponts of two metal balls.P and Q,respectively of masses 55 kg and 70 kg is 80 cm calculate the gravitational force that P exerts on Q answer F=Gm1m2/r^2 F=(6,67x10^-11)(55kg)(70kg)/(80cm) F=4.01x10^-11..... Is it correct is correct (b)give only the ...
*Sunday, October 11, 2015 by angel*

**physics help**

A block of mass 5 kg is place on a table top.it is attached to a mass piece of 2kg by a light string that passes over a frictionless pulley.the table top exerts a frictional force of 7 N on the block. calculate the tension in the string.
*Sunday, October 11, 2015 by happy*

**Physics**

A child climbs up a set of stairs and reaches a height of 2.5m what is the child's gain I potential energy ?
*Sunday, October 11, 2015 by Caroline*

**Physics (Thin Film Interference)**

A layer of transparent plastic (n=1.61) on glass (n=1.52) looks dark when viewed in reflected light whose wavelength is 589 nanometers in vacuum. Find the two smallest possible nonzero values for the thickness of the layer. Answers are 183 nm and 366 but I don't understand...
*Sunday, October 11, 2015 by Richard*

**physics **

In the figure, a radar station detects an airplane approaching directly from the east. At first observation, the airplane is at distance d1 = 350 m from the station and at angle θ1 = 31° above the horizon. The airplane is tracked through an angular change Δθ...
*Sunday, October 11, 2015 by collins *

**physics **

Identical +2.83 μC charges are fixed to adjacent corners of a square. What charge (magnitude and algebraic sign) should be fixed to one of the empty corners, so that the total potential at the remaining empty corner is 0 V? φ =k•q/r φ1+ φ2 + φ3 =0...
*Sunday, October 11, 2015 by james please check correct working*

**physics **

The filament in an incandescent light bulb is made from tungsten (resistivity 5.6 x 10-8 Ù·m). The light bulb is plugged into a 120-V outlet and draws a current of 2.36 A. If the radius of the tungsten wire is 0.00464 mm, how long must the wire be? restivity of ...
*Saturday, October 10, 2015 by james small help plz *

**Physics **

A container holds 1.9 mol of gas. The total average kinetic energy of the gas molecules in the container is equal to the kinetic energy of a 8.0x10-3 kg bullet with a speed of 960 m/s. What is the Kelvin temperature of the gas? do I use the formula? T= (mv^2)/u No 3k
*Saturday, October 10, 2015 by james*

**PHYSICS**

A cart of weight 25 N is released at the top of an inclined plane of length 1m, which makes an angle of 30° with the ground. It rolls down the plane and hits another cart of weight 40 N at the bottom of the incline. Calculate the speed of the first cart at the bottom of ...
*Saturday, October 10, 2015 by VIPIN*

**Physics**

Two forces act on an object. The first force has a magnitude of 19.0 N and is oriented 58.0° counter-clockwise from the x axis, while the 2nd force has x- and y-components (-25.0 N, 16.5 N). Express the magnitude and direction of the net force.
*Saturday, October 10, 2015 by Lc*

**Physics**

Consider a train that rounds a curve with a radius of 574 m at a speed of 160 km/h. Calculate the friction force on the passenger if the train tilts at an angle of 8.0∘ toward the center of the curve.
*Saturday, October 10, 2015 by Kaity*

**physics, please help**

An object of mass m can slide without friction on a tabletop. A horizontal string tied to the object passes through a frictionless hole in the table and is connected to a second, hanging mass, M. If m is put into motion so that it moves in a circular path of radius r, find a) ...
*Saturday, October 10, 2015 by johnny*

**physics**

in the compton scattering event, the scattered photon has an energy of 120 keV and the recoiling e- has an energy of 40 keV. Find the wavelength of the photon.
*Saturday, October 10, 2015 by paul*

**Physics i need hlp i have exams next weeks that is why i post the question that which i cannot do**

The cost C of running a ship on a certain voyage is said to be given by c=av+b/v where v is the average speed in km/h and a,b are constant.find the value of v in terms of a and b to give the maximum cost,and also find the cost???
*Saturday, October 10, 2015 by Collins*

**Physics**

In a rescue, a 74.1 kg police officer is suspended by two cables, as shown in the figure. Cable A makes an angle θA = 32.0° with respect to the horizontal, and cable B, θB = 74.0°. Sketch a free body diagram. Calculate the tension in cable A.
*Saturday, October 10, 2015 by Carol*

**physics **

the velocity of a particle moving along the axis is given for t>0 by v=(32t -2t^3 ) m/s where t is in s what is the acceleration of a particle when (after t=0 ) it achieves its maximum displacement in the positive x direction
*Saturday, October 10, 2015 by nada*

**physics (Compton effect)**

need helppp. Find the energy of an x-ray photon that can impart a maximum energy of 50 keV to an electron by Compton collision. Max energy being Kinetic Energy? do I just plug the 50*10^3 eV (convert to J) into the E=h (c/lambda) equation?? We are not given theta, the incident...
*Saturday, October 10, 2015 by paul*

**Physics **

You can shoot an arrow straight up so that it reaches the top of a 25-m-t building. (a) How far will the arrow travel of you shoot it horizontally while pulling the bow in the same way? The arrow starts 1.45 m above the ground.(b) Where do you need to put a target that is 1.45...
*Saturday, October 10, 2015 by K*

**Physics**

A car decelerates uniformly and comes to a stop after 9 seconds. The car's average velocity during deceleration was 45 km/h. What was the cars deceleration while slowing down?
*Saturday, October 10, 2015 by Joe*

**physics**

Pilots of high-performance fighter planes can be subjected to large centripetal accelerations during high-speed turns. Because of these accelerations, the pilots are subjected to forces that can be much greater than their body weight, leading to an accumulation of blood in the...
*Friday, October 9, 2015 by Regheim Beck*

**physics**

Two satellites are in circular orbits around the earth. The orbit for satellite A is at a height of 427 km above the earth’s surface, while that for satellite B is at a height of 873 km. Find the orbital speed for (a) satellite A and (b) satellite B.
*Friday, October 9, 2015 by Regheim Beck*

**physics**

when starting a foot race a 66 kg sprinter exerts an average force of 640 N backward on the ground for 0.85s. What is his final speed in m/s?
*Friday, October 9, 2015 by Anonymous*

**Child development**

Infants' naïve theory of physics leads them to believe that a.gravity is not important so floating objects are not unusual. b.one object striking a second object does not affect the second object. c.objects cannot move through other objects. d.objects move along ...
*Friday, October 9, 2015 by Woody*

**Child development**

Infants' naïve theory of physics leads them to believe that A.gravity is not important so floating objects are not unusual. b.one object striking a second object does not affect the second object. c.objects cannot move through other objects. objects move along ...
*Friday, October 9, 2015 by Woody*

**physics**

a block of mass 5 kg is position at angle 45 degree ,a force of 10 newton is applied to the block parallel to the ground. is the coefficient of kinetic friction is 0.5 , calculate its acceleration?
*Friday, October 9, 2015 by Amna *

**Physics **

A bullet leaves a rifle with a velocity of 100 m/s and the rifle mass 2.5 kg recoils with a velocity of 1 m/s. Find the mass of the bullet. PLEASEEEE HELP ME.👏
*Friday, October 9, 2015 by Manan Bhattacharya*

**Physics/trig**

A fire hose ejects a stream of water at an angle of 33.6 ° above the horizontal. The water leaves the nozzle with a speed of 29.6 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the highest possible fire?
*Friday, October 9, 2015 by Jenna*

**physics**

On a plot of position x versus time t for an object’s motion, what corresponds to the object’s average velocity between instant t1 and instant t2? (a) intercept of the plot on the horizontal axis (b) intercept of the plot on the vertical axis (c) slope of a line ...
*Friday, October 9, 2015 by ahmed *

**Physics **

A player throws a ball at an initial velocity of 36 m/s. The maximum distance the ball can reach (assume ball is caught at the same height at which it was released) is? (I tried to solve it but i think it doesn't have all the information needed to slove it, but i'm not...
*Friday, October 9, 2015 by Yass*

**physics**

The elastic potential energy E is given by E=C p^2 g^2 A l0^3,where p is the density of the metal.g is the acceleration of free fall. A is the cross-sectional area of the wire and C is a constant. determine the si base units of C?
*Friday, October 9, 2015 by monique*

**physics**

gayle runs at a speed of 4.00 m/s and dives on a sled, initially at rest on the top of a frictionless, snow-covered hill. after she has descended a vertical distance at a 5.00 m, her brother,who is initially at rest, hops on her back, and they continue down the hill together, ...
*Thursday, October 8, 2015 by naome*

**Physics**

A man runs east 9.8 m/s for 11 s, stops for 6.9 s, then runs back (west) at 1.5 m/s for 1.2 s. What is the man's average velocity?
*Thursday, October 8, 2015 by Sean *

**physics**

A hang glider pilot is flying horizontally over an open field when her shoe falls off. She was going 23.0 m/s and was 81.0 m above the ground. How long did it take for the shoe to hit the ground?
*Thursday, October 8, 2015 by sheri*

**Physics**

A ball thrown upward from the a point 7 meters below the bottom of a window rises past the window, which is 2.5 meters high, passing the window in 0.33 seconds. How fast was it going when it reached the bottom of the window, and with what velocity was it initially thrown upward?
*Thursday, October 8, 2015 by Anonymous*

**Physics**

You are standing on the roof of a building 300 m high, and throw a stone upward at 25 m/s. Find the speed of the stone as it strikes the ground.
*Thursday, October 8, 2015 by Jean-Paul*

**science- physics**

A position vector with magnitude 40 m points to the right and up. Its x-component is 32 m . What is the value of its y-component?
*Thursday, October 8, 2015 by Laura*

**Physics**

In the amusement park ride known as Magic Mountain Superman, powerful magnets accelerate a car and its riders from rest to 37.1 m/s in a time of 6.28 s. The mass of the car and riders is 8.88 × 103 kg. Find the average net force exerted on the car and riders by the magnets.
*Thursday, October 8, 2015 by Natasha*

**Physics**

A plane flies at 220 km/h toward the south as observed by a person on the ground. The airplane pilot measures an air velocity of 2.8 x 105 m/h south. What is the velocity of the wind that affects the plane?
*Thursday, October 8, 2015 by Pip*

**physics **

A soccer ball accelerates from rest and rolls 6.5 meters down a hill in 3.1 seconds. It then bumps a tree. What is the speed of the ball right before it hits a tree?
*Thursday, October 8, 2015 by ashley*

**physics **

Block A (Mass = 2.319 kg) and Block B (Mass = 1.870 kg) are attached by a massless string as shown in the diagram. Block A sits on a horizontal tabletop. There is friction between the surface and Block A. The string passes over (you guessed it) a frictionless, massless pulley...
*Thursday, October 8, 2015 by Carly*

**physics **

A 3.90 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=14.1N at an angle theta=32.5degrees above the horizontal, as shown. a.) What is the magnitude of the acceleration of the block when the force is applied? b.) What is the ...
*Thursday, October 8, 2015 by Carly*

**Physics **

Three blocks are located on a horizontal frictionless table. They are connected by a massless cord, as shown in the figure, and pulled to the right. The masses of the three blocks are m1 = 38 kg, m2 = 37 kg, and m3 = 17 kg. a.) The pulling force is equal to T3 = 45 N. What is ...
*Thursday, October 8, 2015 by Carly*

**science- physics**

Find the x- and y-components of the vector d⃗ = (6.0 km , 31 ∘ left of +y-axis). I worked it out and got 5.14, 3.09 and apparently it's wrong, I don't know what I did wrong.
*Thursday, October 8, 2015 by Laura*

**Physics**

a soccer ball is kicked and given an initial velocity of 12m/s at an angle of 30 degrees from the ground what's the velocity of the ball in the x axis
*Thursday, October 8, 2015 by Raesha*

**physics**

Gayle runs at a speed of 3.80 m/s and dives on a sled, initially at rest on the top of a frictionless snow covered hill. After she has descended a vertical distance of 5.00 m, her brother, who is initially at rest, hops on her back and together they continue down the hill. ...
*Thursday, October 8, 2015 by jovelyn trocio*

**physics help**

A block of wood experiences a normal force of 32 N from a rough,flat surface.there is a rope tied to the block.the rope is pulled parallel to the surface and the tension in the rope can be increased to 8 N before the block starts to slide. Determine the coefficient of static ...
*Thursday, October 8, 2015 by john*

**physics help**

Three co-linear forces f1=45 N west,f2=63 N east and an unknown force f3 are applied to an object.The resultant force of the three forces is 12 N west determine the magnitude and direction of the force f3 using an algebric calculation(vector addition) answer fres=f1^2 f2^2 12=...
*Thursday, October 8, 2015 by melissa*

**physics**

a aircraft is flying to north with velocity of 350 m/s, aside wind of velocity 100m/s is blowing due to west. what is the resultant velocity ? what is the direction of resultant velocity? how far this aircraft travels during 1 hour?
*Thursday, October 8, 2015 by ne*

**Physics**

A Canon shoots an artillery shell towards a target 4.54 km distant, where it lands at the same level it was shot. It was noted that the elapsed time of the projectile was 27.5 seconds. What was the muzzle velocity of the shell? (there is a picture showing a canon shooting the ...
*Thursday, October 8, 2015 by Ronald*

**Physics**

A soccer ball is kicked with resultant velocity of 22.6 m/s at an angle of 60 degrees. What is the time to Apex, what is the range of the kick? r = 22.6 angle = 60 degrees 1)Vxi=sin(60)(22.6) = 19.57 Vyi=cos(60)(22.6) = 11.3 2)T= Vyf-Vyi/A 0-11.3/-9.81 = 1.1 sec time to apex ...
*Wednesday, October 7, 2015 by Sean*

**Physics**

A train accelerates from rest at a rate of 4m/s^2 for 5 minutes. Then it continues with constant velocity for 10 minutes. Then it slows down to a complete stop while traveling 200 meters. a. What was the total displacement of the train? b. What was the average velocity for the...
*Wednesday, October 7, 2015 by Pdriz*

**Physics**

The 1.1 kg physics book is connected by a string to a 250 g coffee cup. The book is given a push up the slope and released with a speed of 2.9 m/s . The coefficients of friction are μs =0.50 and μk =0.20. What Distance does it travel up the slope? I drew a free body ...
*Wednesday, October 7, 2015 by Zach*

**Physics**

A gun shoots a bullet at 1200 m/s at an angle of 600 above the horizontal. Neglecting air resistance, determine: a.) its time of flight b.) its range
*Wednesday, October 7, 2015 by Peter*

**Physics**

A helicopter is rising vertically at a uniform velocity of 14.7 m/s. When it is 196m from the ground, a ball is projected from it with a horizontal velocity of 8.5 m/s with respect to the helicopter. Calculate: a.) when the ball will reach the ground b.) where it will hit the ...
*Wednesday, October 7, 2015 by Eleanor*

**Physics **

While playing lawn darts with his friend, Jack notices that when he throws a dart up at 60 degrees it travels 11 meters. How high did the dart travel
*Wednesday, October 7, 2015 by Autumn *

**Physics**

A child rides a toboggan down a hill that descends at an angle of 26.6 degrees to the horizontal. The hill is 13.1 meters long. What is the vertical component of the child's displacement? Answer in units of meters.
*Wednesday, October 7, 2015 by Emily Peterson*

**Algebra**

A golf ball is hit with an initial velocity of 140 ft per second at an inclination of 45 degrees to the horizontal. In physics, it is established that the height h of the golf ball is given by the function h(x)=-32x^2/140^2+x, How far does the golf ball travel before it...
*Wednesday, October 7, 2015 by mu*

**physics**

A shopper pushing a cart through a store moves 30.0 m south down one aisle, then makes a 90◦ turn and moves 11.0 m. He then makes another 90◦ turn and moves 22.0 m. What is the magnitude of the smallest possible displacement the shopper could have? You are not ...
*Wednesday, October 7, 2015 by bianca*

**physics**

The steel I-beam in the drawing has a weight of 1.53 × 103 N and is being lifted at a constant velocity. What is the tension in each cable attached to its ends?
*Wednesday, October 7, 2015 by Anonymous*

**Physics**

How much work did the movers do to push a 49.0 kg crate 10.3 m across a rough floor at a speed of 2.9 m/s with a horizontal pushing force of 48 N ?
*Wednesday, October 7, 2015 by Help*

**Physics **

Draw a free body diagram and Apply Newton's 2nd law in both direction. 60 kg chair is pulled along a rough horizontal surface under the action of a 200N force 30 degrees up from horizontal, as shown the acceleration of the chair is 1.5 m/s^2. a) Determine the normal force ...
*Wednesday, October 7, 2015 by Matt*

**Physics**

A hot-air balloon is rising upward with a constant speed of 2.65 m/s. When the balloon is 3.40 m above the ground, the balloonist accidentally drops a compass over the side of the balloon. How much time elapses before the compass hits the ground?
*Wednesday, October 7, 2015 by DJ*

**Physics**

In lacrosse, a ball is thrown from a net on the end of stick by rotating the stick and forearm about the elbow. If the angular velocity of the ball about the elbow joint is 26.5 rad / s and the ball is 1.35 m from the elbow joint, what is the velocity of the ball?
*Wednesday, October 7, 2015 by Nico *

**physics**

A skateboarder, with an initial speed of 3.2 m/s , rolls virtually friction free down a straight incline of length 16 m in 3.3 s. At what angle θ is the incline oriented above the horizontal?
*Wednesday, October 7, 2015 by gal*

**physics**

In the amusement park ride known as Magic Mountain Superman, powerful magnets accelerate a car and its riders from rest to 43.7 m/s in a time of 6.50 s. The mass of the car and riders is 3.24 × 103 kg. Find the average net force exerted on the car and riders by the magnets.
*Wednesday, October 7, 2015 by sandra*

**Physics**

A boat moving at 5 mi/h is to cross a river in which the current is flowing at 3 mi/h. In what direction should the boat head to reach a point on the other bank of the river directly opposite the starting point?
*Wednesday, October 7, 2015 by J*

**Physics**

A block of mass 2.30kg is accelerated across a rough surface by a rope passing over a pulley. a) The tension in the rope is 12.4N, and the pulley is 11.2cm above the top of the block. The coefficient of kinetic friction is 0.415. Determine the acceleration of the block when x...
*Wednesday, October 7, 2015 by Presley*

**Physics**

An artillery crew demonstrates its skill by firing a shell at an angle of 69 deg and then lowering the gun barrel and firing a second shell at a smaller angle of 22 deg in such a way that the two shells collide in midair. The initial velocity of the shells is 900 m/s. Find the...
*Wednesday, October 7, 2015 by Madeleine*

**Physics**

A skier leaves the ramp of a ski jump with a velocity of 12.6m/s, 14.5° above the horizontal. The slope below is inclined downwards at 52.2°, and air resistance is negligible. a)Calculate the distance from the ramp to where the jumper lands. b) Calculate the velocity ...
*Wednesday, October 7, 2015 by Madie*

**Physics**

Suppose you have a stack of 9 identical oak planks, each of which have a mass of 8.0 kg. You are required to pull the seventh plank from the stack (counting from the top). If the coefficient of friction between oak and oak is 0.6, how hard do you have to pull?
*Wednesday, October 7, 2015 by Kristin*

**Physics**

A block of mass 8.60 kg is pulled along a horizontal frictionless surface by a cord that exerts a force of 33 N at an angle 29.40 degrees from the horizontal. What is the magnitude of the normal force exerted on the mass by the floor? I solved for the acceleration, which was 3...
*Wednesday, October 7, 2015 by Kristin*

**Physics**

Light in a vacuum is incident on a transparent glass slab. The angle of incidence is 35.1°. The slab is then immersed in a pool of liquid. When the angle of incidence for the light striking the slab is 21.1°, the angle of refraction for the light entering the slab is ...
*Tuesday, October 6, 2015 by Anonymous*

**Physics **

A car with a velocity of 21m/s is accelerated uniformly at arate of 1.6m/s for 6.8s. What is its final velocity?
*Tuesday, October 6, 2015 by Mike*

**Physics **

A ball of mass 0.6 kg, initially at rest, is kicked directly toward a fence from a point 20 m away. The velocity of the ball as it leaves the kicker's foot is 17 m/s at angle of 45 degrees above the horizontal. The top of the fence is 6m high. The ball hits nothing while ...
*Tuesday, October 6, 2015 by Sarah *

**Physics **

A stone is thrown from ground level at 72 m/s. Its speed when it reaches its highest point is 46 m/s. Find the angle, above the horizontal, of the stone's initial velocity. Answer in units of degree
*Tuesday, October 6, 2015 by Jordan *

**Physics**

A baseball is thrown at an angle of 29 degrees relative to the ground at a speed of 24.3 m/s. The ball is caught 51.0463 m from the thrower. The acceleration due to gravity is 9.81 m/s2 How high is the tallest spot in the ball's path? Answer in units of m
*Tuesday, October 6, 2015 by Jessica*

**Physics**

A 0.3 kg tennis ball is travelling west with a speed of 4 m/s and bounces off a wall. After bouncing, the ball is travelling east at 2 m/s. The tennis ball was in contact with the wall for 0.004 seconds. a) What is the initial and final momentum of the ball? b) What is the ...
*Tuesday, October 6, 2015 by Jasmine*

**Physics**

An object is thrown vertically up with a speed of 15m/s. How much time passes before it comes down at 15m/s? (air resistance is negligible)
*Tuesday, October 6, 2015 by Mahmoud*

**Physics**

A football is kicked at ground level with a speed of 15.0 m/s at an angle of 39.0° to the horizontal. How much later does it hit the ground?
*Tuesday, October 6, 2015 by Suhaila*

**Physics**

A 0.3 kg tennis ball is travelling west with a speed of 4 m/s and bounces off a wall. After bouncing, the ball is travelling east at 2 m/s. The tennis ball was in contact with the wall for 0.004 seconds. a) What is the initial and final momentum of the ball? b) What is the ...
*Tuesday, October 6, 2015 by Jasmine*

**physics**

A car travels in a straight line for 4.6 h at a constant speed of 95 km/h . What is its acceleration?
*Tuesday, October 6, 2015 by Anonymous *