Tuesday

October 21, 2014

October 21, 2014

**Recent Homework Questions About Physics**

Post a New Question | Current Questions

**physics help please**

An airplane has an air speed of 112m/s [N 20 degrees W] and has a ground speed of 106 m/s [N 25 degrees W]. Find the velocity of the wind.
*Sunday, September 28, 2014 at 9:49pm*

**Physics help please **

A student swims at 4m/s. She is swimming from west to east across a river that's is flowing 2.2m/s [S]. A) if the river is 100 m wide, what is the quickest time that she can swim the entire width? B) how far downstream will she be? C) if she decides to go directly across ...
*Sunday, September 28, 2014 at 9:48pm*

**physics**

An electron in the cathode ray tube of a tele- vision set enters a region where it acceler- ates uniformly from a speed of 30100 m/s to a speed of 3.82 × 106 m/s in a distance of 2.97 cm. What is its acceleration? Answer in units of m/s2
*Sunday, September 28, 2014 at 9:33pm*

**physics**

A hunter wishes to cross a river that is 1.0 km wide and that flows with a speed of 4.9 km/h. The hunter uses a small powerboat that moves at a maximum speed of 9.6 km/h with respect to the water. What is the minimum time necessary for crossing?
*Sunday, September 28, 2014 at 9:24pm*

**physics**

An electron, starting from rest and moving with a constant acceleration, travels 5.8 cm in 14 ms. What is the magnitude of this acceleration? Answer in units of km/s2
*Sunday, September 28, 2014 at 9:23pm*

**physics**

You and a friend stand on a snow-covered roof. You both throw snowballs from an elevation of 18 m with the same initial speed of 11 m/s, but in different directions. You through your snowball downward, at 40° below the horizontal; your friend throws her snowball upward, at...
*Sunday, September 28, 2014 at 9:08pm*

**Physics**

A swimmer, capable of swimming at a speed of 1.44 m/s in still water (i.e., the swimmer can swim with a speed of 1.44 m/s relative to the water), starts to swim directly across a 2.21-km-wide river. However, the current is 0.840 m/s, and it carries the swimmer downstream. (a) ...
*Sunday, September 28, 2014 at 8:53pm*

**Physics**

A student swims at 4m/s. She is swimming from west to east across a river that's is flowing 2.2m/s [S]. A) if the river is 100 m wide, what is the quickest time that she can swim the entire width? B) how far downstream will she be? C) if she decides to go directly across ...
*Sunday, September 28, 2014 at 8:52pm*

**Physics**

A tennis ball connected to a string is spun around in a vertical, circular path at a uniform speed. The ball has a mass m = 0.162 kg and moves at v = 4.73 m/s. The circular path has a radius of R = 0.87 m 1)What is the magnitude of the tension in the string when the ball is at...
*Sunday, September 28, 2014 at 8:48pm*

**physics**

A radar antenna is tracking a satellite orbiting the earth. At a certain time, the radar screen shows the satellite to be 118 km away. The radar antenna is pointing upward at an angle of 58.2 ° above the ground. Find (a) the x and (b) the y components (in km) of the ...
*Sunday, September 28, 2014 at 8:47pm*

**physics**

An airplane has an air speed of 112m/s [N 20 degrees W] and has a ground speed of 106 m/s [N 25 degrees W]. Find the velocity of the wind.
*Sunday, September 28, 2014 at 8:41pm*

**Physics**

A force F acts to the right on a 4.81 kg block. A 2.53 kg block is stacked on top of the 4.81 kg block and can slide on it with a coefficient of friction of 0.2 between the blocks. The table has a coefficient of friction of 0.23. The acceleration of gravity is 9.8 m/s 2 . The ...
*Sunday, September 28, 2014 at 8:30pm*

**physics**

A car is moving with a velocity od 10.1m/s [N] while on a ferry that is moving across a lake.if an observer on shore measures the velocity of the car to be 29m/s [N] how quickly is the ferry moving?
*Sunday, September 28, 2014 at 8:25pm*

**physics**

A grasshopper jumps a horizontal distance of 1m from rest, with an initial velocity at a 45 degree angle with respect to the horizontal. Find the initial speed of the grasshopper and the maximum height reached.
*Sunday, September 28, 2014 at 7:38pm*

**Physics HELP**

A ball is thrown horizontally at 15 m/s from a clifftop 60 m above the sea level. Find: a) the time to land; b) the angle at which it hits the water; ° below the horizontal c) the speed at which it hits the water.
*Sunday, September 28, 2014 at 7:24pm*

**physics**

You and your friend are on the roof of a 20 m tall building investigating a free fall. Your friend releases a small rock from rest. You throw another rock simultaneously with your friend aiming it straight down. (a) What initial speed should you supply to the rock so it hits ...
*Sunday, September 28, 2014 at 7:07pm*

**physics**

Car a starts from rest and speeds up with constant accelleration until it reaches its max speed. Car b starts from rest, at the moment car a is at max speed, and speeds up with constant acceleration. How much time elapses between when car b starts moving, and car b passes car ...
*Sunday, September 28, 2014 at 7:02pm*

**Physics**

A ball is thrown at 41° below the horizontal from a rooftop of height 65 m. It lands 2 s later. Find: Find: a) its initial speed b) the point of impact with the ground; m from the base of the building c) the angle at which it hits the ground. ° below the horizontal
*Sunday, September 28, 2014 at 6:25pm*

**Physics**

A freight train has a mass of 1.3 x10^7 kg. if the locomotive can exert a constant pull of 5.4x10^5 N, how long would it take to increase the speed of the train from rest to 71 km/h? Disregard friction. Answer in units of s.
*Sunday, September 28, 2014 at 6:11pm*

**physics**

a tourist being chased by an angry bear is running in a straight line toward his car at a speed of 4.0m/s. the car is d distance away. the bear is 26.0m behind the tourist and running at 6.0m/s. the tourist reaches the car safely. what is the maximum possible value for d.
*Sunday, September 28, 2014 at 5:45pm*

**physics**

A football is kicked off with an initial speed of 65 ft/s at a projection angle of 45 degrees. A receiver on the goal line 63 yd away in the direction of the kick starts running to meet the ball at that instant. What must be his minimum speed (in feet/second) if he is to catch...
*Sunday, September 28, 2014 at 5:44pm*

**physics**

A small relief package is dropped by a helicopter that is descending steadily at 2.0 m/s. a) After 2.5 s, what is the speed of the relief package? b) After 2.5 s, how is the package below the helicopter? I think I need to use the kinematic equations.
*Sunday, September 28, 2014 at 5:41pm*

**Physics **

A system absorbs 1000 Joules of heat and delivers 600 Joules of work, while loosing 100 Joules of heat by conduction to the atmosphere, the change in the internal energy of the system will be. My solution. I used U=Q+A, and my answer was 1600, but its real answer is 300 Joules...
*Sunday, September 28, 2014 at 4:59pm*

**physics**

A robot probe drops a camera off the rim of a 457 m high cliff on Mars, where the free-fall acceleration is 3.7 m/s2. find the time required for the camera to reach the ground. answer in units of s. i dont know if my equation is right: * tfinal= (vinitial + g)(vfinal)
*Sunday, September 28, 2014 at 4:48pm*

**Physics**

Consider two toy cars. Car A starts from rest and speeds up with constant acceleration for a time delta t until it reached a speed of v and then continues to travel at this speed. At the moment car A reaches its maximum speed, car B, starting at rest from the same point that ...
*Sunday, September 28, 2014 at 4:38pm*

**physics**

A rocket blasts off from rest and attains a speed of 59.4 m/s in 14.1 s. An astronaut has a mass of 66.7 kg. What is the astronaut's apparent weight during takeoff?
*Sunday, September 28, 2014 at 4:35pm*

**physics**

A Student drops a rock from a bridge to the water 14.7m below. with what speed does the rock strike the water? the acceleration of gravity is 9.8 m/s^2. andswer in units of m/s.
*Sunday, September 28, 2014 at 4:25pm*

**Physics**

A bullet is fired straight up from a gun with a muzzle velocity of 312 m/s. Neglecting air resistance, what will be its displacement after 1.4 s? The acceleration of gravity is 9.8 m/s 2 .
*Sunday, September 28, 2014 at 4:16pm*

**physics**

A ball is thrown horizontally at 15 m/s from a clifftop 60 m above the sea level. Find: a) the time to land; b) the angle at which it hits the water; ° below the horizontal c) the speed at which it hits the water. m/s
*Sunday, September 28, 2014 at 3:16pm*

**Physics**

A robot probe drops a camera off the rim of a 429 m high cliff on Mars, where the free-fall acceleration is 3.7 m/s2. What equation will be appropriate to find velocity?
*Sunday, September 28, 2014 at 2:59pm*

**Physics**

Consider two toy cars. Car A starts from rest and speeds up with constant acceleration for a time delta t until it reached a speed of v and then continues to travel at this speed. At the moment car A reaches its maximum speed, car B, starting at rest from the same point that ...
*Sunday, September 28, 2014 at 2:40pm*

**Physics**

A meter stick weighs 200 grams and is supported at the center. Three masses of 100, 200, and 150 grams are placed respectively, at the 10-cm, 20-cm and 60 cm points of the meter stick. To balance the meter stick, where must a 300 grams weight be placed on the meter stick?
*Sunday, September 28, 2014 at 2:35pm*

**Physics help please**

A gamma ray with 700KeV energy is Compton-Scattered from an electron. Find the energy of the photon scattered at 110 degrees, the energy of the scattered electron, and the recoil angle of the electron mp=mass of proton=1.673x10^-27 λ=h/mpc(1-cosθ) λ=(6.6261x10^-...
*Sunday, September 28, 2014 at 2:24pm*

**physics**

A bullet is fired straight up from a gun with a muzzle velocity of 214 m/s. Neglecting air resistance, what will be its displacement after 8.2 s? The acceleration of gravity is 9.8 m/s2 . Answer in units of m
*Sunday, September 28, 2014 at 2:19pm*

**Physics**

A plane with a velocity of 111. 9 meters per second at a maximum rate of 6.8 m/s^2 the plane touches the runaway what's the minimum time before it can come to rest? A=6.8m/s^2 V=111.9m/s t=?
*Sunday, September 28, 2014 at 2:18pm*

**Physics**

A tennis ball connected to a string is spun around in a vertical, circular path at a uniform speed. The ball has a mass m = 0.162 kg and moves at v = 4.73 m/s. The circular path has a radius of R = 0.87 m 1)What is the magnitude of the tension in the string when the ball is at...
*Sunday, September 28, 2014 at 1:43pm*

**Physics**

Two rocks are thrown simultaneously from the top of a very tall tower with identical speeds of v = 7.70 m/s, but in two different directions.One of them is thrown with an angle of 10.0 degrees below the horizontal, the other one at an angle of 50.0 degrees above the horizontal...
*Sunday, September 28, 2014 at 1:41pm*

**Physics**

A small, single engine airplane is about to take off. The airplane becomes airborne, when its speed reaches 117.0 km/h. The conditions at the airport are ideal, there is no wind. When the engine is running at its full power, the acceleration of the airplane is 2.40 m/s2. What ...
*Sunday, September 28, 2014 at 1:38pm*

**Physics**

An electron in an atom has a speed of 2.2 × 10^6 m/s and orbits the nucleus at a distance of 5 × 10^-11m.a)What is its centripetal acceleration? b)A neutron star of radius 17 km is found to rotate at 5 revolutions per second. What is the centripetal acceleration of...
*Sunday, September 28, 2014 at 11:52am*

**physics**

An electron in an atom has a speed of 2.2 × 10^6 m/s and orbits the nucleus at a distance of 5 × 10^-11m.a)What is its centripetal acceleration? b)A neutron star of radius 17 km is found to rotate at 5 revolutions per second. What is the centripetal acceleration of...
*Sunday, September 28, 2014 at 10:52am*

**physics**

The figure below shows a train with 3 compartments only. Each of the compartments has a mass of 30 tons . Two of them are motor cars while the other one is a trailer car. Each of the motor cars provides a driving force F. Suppose the train is accelerating at 1.5 m s−2 ...
*Sunday, September 28, 2014 at 7:24am*

**Physics**

A stone is thrown vertically upward from the top of the tower with a velocity of 15m / s. Two seconds later a second stone is dropped from the top of the tower.if both the stone strike the ground simultaneously find the height of the tower
*Sunday, September 28, 2014 at 6:01am*

**physics**

To tighten a bolt, you push with a force of 84N at the end of a wrench handle that is 0.24m from the axis of the bolt. If you move your hand inward to be only 0.10 m from the bolt, find the force that you should exert to achieve the same torque.
*Sunday, September 28, 2014 at 4:26am*

**physics**

To tighten a bolt, you push with a force of 84N at the end of a wrench handle that is 0.24m from the axis of the bolt. What torque are you exerting?
*Sunday, September 28, 2014 at 4:25am*

**physics**

A person whose mass is m = 60.5 kg steps on a mechanical bathroom scale placed on an inclined plane that makes the angle α = 31.7° with the horizontal. What is the reading on the scale? For this question I used the formula FN=mgcostetha= 60.5x9.8xcos31.7 but the ...
*Sunday, September 28, 2014 at 3:27am*

**physics**

A cube of mass m1 = 7.7 kg is sitting on top of another cube of the same size and mass m2 = 0.6 kg while they are both in free-fall. Ignoring any air resistance, what is the magnitude of the normal force with which the bottom cube is acting on the top cube? for this question. ...
*Sunday, September 28, 2014 at 3:25am*

**Physics**

an object is located a distance d above the surface of a large planet of radius r. at this position, its true weight is one percent less than its true weight on the surface. what is the ratio of d/r?
*Sunday, September 28, 2014 at 1:20am*

**Physics**

A car travels 120 meters in one direction in 20 seconds. Then the car returns ¾ of the way back in 10 seconds. a) Calculate the average speed of the car for the first part of the trip. b) Find the average velocity of the car.
*Saturday, September 27, 2014 at 11:09pm*

**physics**

If the acceleration due to gravity on the Moon is 1/6 that what is on the Earth, what would a 100 kg man weight on the Moon? If a person tried to simulate this gravity in an elevator, how fast would it have to accelerate and in which direction?
*Saturday, September 27, 2014 at 10:56pm*

**physics**

A small toy airplane is flying in the xy-plane parallel to the ground. In the time interval t=0 to t=10.0 s, its velocity as a function of time is given by υ⃗ =(1.50m/s2)ti^+[13.0m/s−(2.00m/s2)t]j^.
*Saturday, September 27, 2014 at 10:48pm*

**physics**

If a 1500 kg car stopped from an in 5.6 seconds with an applied force of 5000 N, how fast was it initially traveling?
*Saturday, September 27, 2014 at 10:46pm*

**physics**

A small toy airplane is flying in the xy-plane parallel to the ground. In the time interval t=0 to t=10.0 s, its velocity as a function of time is given by
*Saturday, September 27, 2014 at 10:46pm*

**physics**

Student wants to jump from their 3rd floor apartment window to the swimming pool below. The base of the apartment is 8.00 meters from the pool’s edge. If the window is 20.0 meters high, how fast does the student have to be running horizontally to make sure they make it to...
*Saturday, September 27, 2014 at 10:40pm*

**physics**

The roadway bridge over a canal is in the form of an arc of circle of radius what is the maximum car can cross the bridge with the ground at the highest point
*Saturday, September 27, 2014 at 10:29pm*

**physics**

An airplane is 50,000 m above an observer and 2.1 km to the west of them and 1.5 km to the north of you. Determine the angle to the plane in the x – y axis and the total distance to the plane from you. Choose the x-axis east, y axis north, and z axis up.
*Saturday, September 27, 2014 at 10:25pm*

**physics**

5pi over 4
*Saturday, September 27, 2014 at 10:11pm*

**physics**

It takes the elevator in a skyscraper 4.5s to reach its cruising speed of 11m/s . A 70kg passenger gets aboard on the ground floor. What is the passenger's weight before the elevator starts moving? What is the passenger's weight while the elevator is speeding up?
*Saturday, September 27, 2014 at 9:53pm*

**physics**

A satellite is in a circular orbit around an unknown planet. The satellite has a speed of 1.75 104 m/s, and the radius of the orbit is 5.15 106 m. A second satellite also has a circular orbit around this same planet. The orbit of this second satellite has a radius of 8.75 106 ...
*Saturday, September 27, 2014 at 8:52pm*

**ap physics**

2.7s , how far do you travel during this inattentive period?
*Saturday, September 27, 2014 at 7:56pm*

**physics**

An electron in an atom has a speed of 2.2 × 10^6 m/s and orbits the nucleus at a distance of 5 × 10^-11m.a)What is its centripetal acceleration? b)A neutron star of radius 17 km is found to rotate at 5 revolutions per second. What is the centripetal acceleration of...
*Saturday, September 27, 2014 at 7:44pm*

**physics**

In a TV set, an electron beam moves with horizontal velocity of 2.5 × 107 m/s across the cathode ray tube and strikes the screen, 44 cm away. The acceleration of gravity is 9.8 m/s2 . How far does the electron beam fall while traversing this distance? Answer in units of m
*Saturday, September 27, 2014 at 7:00pm*

**Physics**

A police car is traveling at a velocity of 20.0 m/s due north, when a car zooms by at a constant velocity of 44.0 m/s due north. After a reaction time 0.700 s the policeman begins to pursue the speeder with an acceleration of 6.00 m/s^2. Including the reaction time, how long ...
*Saturday, September 27, 2014 at 6:34pm*

**physics**

A basketball player throws the ball at a 53degree angle above the horizontal to a hoop which is located a horizontal distance L = 2.4 m from the point of release and at a height h = 0.9 m above it.What is the required speed if the basketball is to reach the hoop?
*Saturday, September 27, 2014 at 6:22pm*

**physics**

A stone is thrown at 15 m/s an angle \theta below the horizontal from a cliff of height H. It lands 78 m from the base 6 s later. Find \theta and H.
*Saturday, September 27, 2014 at 5:15pm*

**physics**

A ball is thrown at 14 m/s at 57° above the horizontal. Someone located 30 m away along the line3 of the path starts to run just as the ball is thrown. How fast, and in which direction, must the catcher run to catch the ball at the level from which it was thrown?
*Saturday, September 27, 2014 at 5:00pm*

**physics**

A block of mass m = 3.60 kg is pushed a distance d = 2.60 m along a frictionless, horizontal table by a constant applied force of magnitude F = 11.0 N directed at an angle è = 28.0° below the horizontal as shown in the figure below.
*Saturday, September 27, 2014 at 4:03pm*

**physics**

The barrel of a rifle has a length of 0.97m. A bullet leaves the muzzle of a rifle with a speed of 601m/s. What is the acceleration of the bullet while in the barrel?
*Saturday, September 27, 2014 at 3:34pm*

**physics**

A spacecraft is in orbit close to the moon's surface. The centripetal acceleration is 1.6 m/s^2. If the radius of the moon is about 1.7 x 10^6 m, determine: a)the orbital speed b)the period of the orbit
*Saturday, September 27, 2014 at 3:27pm*

**physics**

A pot with a flower falls out of a window box in a tall apartment building. It passes the top of a particular window with a velocity of -1.7 m/s. It passes the bottom of this window 0.2800 s later? How tall is the window (watch sign)?
*Saturday, September 27, 2014 at 3:21pm*

**physics**

A ball falls 5.00 m to the ground. It remains in contact with the ground for 0.027 s and then rebounds to a maximum height of 1.61 m. What acceleration did the ball experience while it was in contact with the ground?
*Saturday, September 27, 2014 at 3:19pm*

**Physics**

Consider two toy cars. Car A starts from rest and speeds up with constant acceleration for a time delta t until it reached a speed of v and then continues to travel at this speed. At the moment car A reaches its maximum speed, car B, starting at rest from the same point that ...
*Saturday, September 27, 2014 at 3:10pm*

**physics**

A geosynchronous satellite is one that appears to be fixed in the sky, a condition useful for telecommunications. If such a satellite orbits the earth at an altitude of 33000 km above the earth's surface, what is its centripetal acceleration? The radius of the Earth is ...
*Saturday, September 27, 2014 at 1:19pm*

**physics**

A basketball is thrown at 45° to the horizontal. The hoop is located 4.4 m away horizontally at a height of 1.1 m above the point of release. What is the required initial speed?
*Saturday, September 27, 2014 at 1:18pm*

**physics**

A state trooper chases a speeder along a straight road; both vehicles move at 160 km/h. The siren on the trooper's vehicle produces sound at frequency of 500 Hz. What is the Doppler shift in the frequency heard by the speeder?
*Saturday, September 27, 2014 at 12:34pm*

**physics**

An ambulance with a siren emitting a whine at 1600 Hz overtaken and passes a cyclist pedaling a bike at 2.44 m/s. After being passed, the cyclist hears a frequency of 1590 Hz. How fast is the ambulance moving?
*Saturday, September 27, 2014 at 12:25pm*

**physics**

An acoustic burglar alarm consists of a source emitting waves of frequency 28.0 kHz. What is the beat frequency between the source waves and the waves reflected from an intruder walking at an average speed of 0.095 m/s directly away from the alarm?
*Saturday, September 27, 2014 at 12:16pm*

**physics**

. A 90cm uniform lever has a load of 30N suspended at 15cm from one of its ends. If the fulcrum is at the centre of gravity, calculate the force that must be applied at its other end to keep it horizontal
*Saturday, September 27, 2014 at 12:00pm*

**physics**

A satellite of mass 205 kg is launched from a site on Earth's equator into an orbit at 200 km above the surface of Earth. (a) Assuming a circular orbit, what is the orbital period of this satellite? s (b) What is the satellite's speed in its orbit? m/s (c) What is the ...
*Saturday, September 27, 2014 at 11:48am*

**physics**

A car travelling at 60 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 67 cm (with respect to the road) while being brought to rest by an inflated air bag. What force (assumed constant) acts on the passenger¡¦s upper torso, which ...
*Saturday, September 27, 2014 at 11:26am*

**physics**

The mass of a robot is 6930 kg. This robot weighs 2520 N more on planet A than it does on planet B. Both planets have the same radius of 3.01 × 106 m. What is the difference MA - MB in the masses of these planets?
*Saturday, September 27, 2014 at 3:35am*

**Physics**

A bike wheels rotate 4 revolutions. How radiant has it rotates?
*Saturday, September 27, 2014 at 1:43am*

**physics**

A rocket moves upward, starting from rest with an acceleration of 25.0 m/s2 for 3.77 s. It runs out of fuel at the end of the 3.77 s but does not stop. How high does it rise above the ground I`ve been sick last week, not quite sure where to even start can you give me a formula...
*Friday, September 26, 2014 at 11:55pm*

**Physics**

A ball is thrown at 15.5 m/s at 42° above the horizontal. Someone located 30 m away along the line3 of the path starts to run just as the ball is thrown. How fast, and in which direction, must the catcher run to catch the ball at the level from which it was thrown?
*Friday, September 26, 2014 at 10:53pm*

**physics**

A hockey puck slides with an initial speed of 52.3 m/s on a large frozen lake. If the coefficient of kinetic friction between the puck and the ice is 0.02, what is the speed of the puck after 11.8 s?
*Friday, September 26, 2014 at 9:30pm*

**Physics**

Your new designer chair has an S-shaped tubular metal frame that behaves just like a spring with the spring constant 13500 N/m. When your friend, who weighs 910 N, sits on the chair, how far does it bend?
*Friday, September 26, 2014 at 4:58pm*

**physics**

A bullet is fired vertically upward from a gun and reaches a height of 7000 ft. Find its initial velocity. How long does it take to reach its maximum height? How long is it in flight?
*Friday, September 26, 2014 at 4:56pm*

**Physics**

A rock is dropped from a bridge to the water below. It takes 2.40 s for the rock to hit the water. Find the speed (in m/s) of the rock as it hits the water. How high (in metres) is the bridge above the water?
*Friday, September 26, 2014 at 4:33pm*

**Physics**

A skateboarder, with an initial speed of 2.4m/s , rolls virtually friction free down a straight incline of length 19m in 3.3 s.At what angle θ is the incline oriented above the horizontal?
*Friday, September 26, 2014 at 3:57pm*

**physics**

A student standing on the ground throws a ball straight up. The ball leaves the student's hand with a speed of 19.0m/s when the hand is 1.50m above the ground. How long is the ball in the air before it hits the ground? (The student moves her hand out of the way.)
*Friday, September 26, 2014 at 2:11pm*

**Physics**

Two rockets are flying in the same direction and are side by side at the instant their retrorockets fire. Rocket A has an initial velocity of +4800 m/s, while rocket B has an initial velocity of +9000 m/s. After a time t both rockets are again side by side, the displacement ...
*Friday, September 26, 2014 at 1:05pm*

**Physics**

From the top of a cliff, a person uses a slingshot to fire a pebble straight downward, which is the negative direction. The initial speed of the pebble is 7.56 m/s. (a) What is the acceleration (magnitude and direction) of the pebble during the downward motion? (b) After 0.950...
*Friday, September 26, 2014 at 1:04pm*

**Physics**

A horizontal force of 3,000,000 dynes can keep a 50 kg mass in uniform motion. What is the coefficient of the kinetic friction? At what angle must the plane be tilted to allow the mass to slide?
*Friday, September 26, 2014 at 12:01pm*

**Physics =/**

Two horizontal forces, and , are acting on a box, but only is shown in the drawing. can point either to the right or to the left. The box moves only along the x axis. There is no friction between the box and the surface. Suppose that = +5.6 N and the mass of the box is 3.1 kg...
*Friday, September 26, 2014 at 11:03am*

**Physics**

A baseball is thrown upward with a velocity of 15m/s. How fast is it moving after 2 seconds? I have no Idea how to begin and the formula he gave us isn't even related to the question at all. (V=vi+at)
*Friday, September 26, 2014 at 10:39am*

**physics**

A power line 10 meter high carries a current 200 amperes .Find the magnetic field of the wire at ground?
*Friday, September 26, 2014 at 8:50am*

**PHYSICS**

an airplane and a helicopter leave an airport in montana at the same time.The aircrafts velocities:v=225mph@20 degree,and v=102mph@49 degree.If these velocities are maintained which craft will cross the borderinto canada first? or do they arrive at the same time. Try the ...
*Friday, September 26, 2014 at 3:28am*

**AP Physics**

a weather station releases a weather balloon.The balloon's buoyancy accelerates it upward at 15m/s sq.At the same time,a wind accelerates it horizontally to the right at 6.5m/s sq.What is the resulting acceleration
*Friday, September 26, 2014 at 2:52am*

**physics**

A robot probe drops a camera off the rim of a 387 m high cliff on Mars, where the free-fall acceleration is 3.7 m/s2 . Find the velocity with which it hits the ground. Answer in units of m/s
*Friday, September 26, 2014 at 12:49am*

**Physics**

4. A ball is kicked toward a fence from a point 32 meters away. The velocity of the ball as it leaves the kicker’s foot is 24 m/s at an angle of 37 degrees above the horizontal. The top of the fence is 2.0 meters high. Assuming air resistance to be negligible…(1 ...
*Thursday, September 25, 2014 at 11:44pm*

**physics**

A duck has a mass of 2.2 kg. As the duck paddles, a force of 0.11 N acts on it in a direction due east. In addition, the current of the water exerts a force of 0.12 N in a direction of 50° south of east. When these forces begin to act, the velocity of the duck is 0.12 m/s ...
*Thursday, September 25, 2014 at 11:06pm*

Pages: <<Prev | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | **9** | 10 | 11 | 12 | 13 | 14 | 15 | Next>>

Post a New Question | Current Questions