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August 21, 2014

Homework Help: Science: Physics

Recent Homework Questions About Physics

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Physics
Two blocks move along a linear path on a nearly frictionless air track. One block, of mass 0.120 kg, initially moves to the right at a speed of 4.90 m/s, while the second block, of mass 0.240 kg, is initially to the left of the first block and moving to the right at 7.40 m/s. ...
Thursday, October 18, 2012 at 6:21pm

physics
A skier starts from rest at the top of a hill. The skier coasts down the hill and up a second hill, as the drawing illustrates. The crest of the second hill is circular, with a radius of 38.1 m. Neglect friction and air resistance. What must be the height h of the first hill ...
Thursday, October 18, 2012 at 6:07pm

physics
Why is this following situation impossible? A normally proportioned adult walks briskly along a straight line in the +x direction, standing straight up and holding his right arm vertical and next to his body so that the arm does not swing. His right hand holds a ball at his ...
Thursday, October 18, 2012 at 6:04pm

Physics
Roughly how high could a 370 K copper ball lift itself if it could transform all of its thermal energy into work? Assume specific heat for copper equal to 386 J/kg·K.
Thursday, October 18, 2012 at 5:51pm

Force Physics
A block with a mass of 12 kg and a sphere with a mass of 10 kg is suspended by two spring scales. What is the reading on the top and bottom scale?
Thursday, October 18, 2012 at 5:39pm

Physics
Joyce and Efua are skating. Joyce pushes Efua, whose mass is 40 kg, with a force of 16 N. The force of friction between Efua's skates and the ice is 2 N. What is the magnitude of the net force exerted by Joyce on Efua?
Thursday, October 18, 2012 at 5:31pm

Physics
Hung vertically, a mass less spring extends by 3.00 cm a mass of 739. G is attached to its lower end. The same mass and spring are then placed apart on a table. The spring is fixed in place and then the mass is given a velocity of 0.900 m/s towards the spring. a) What is the ...
Thursday, October 18, 2012 at 5:26pm

Physics- Elena please help!
A 20.0 g bullet is fired horizontally into a 85 g wooden block that is initially at rest on a frictionless horizontal surface and connected to a spring having spring constant 156 N/m. The bullet becomes embedded in the block. The bullet block system compresses the spring by a ...
Thursday, October 18, 2012 at 5:01pm

PHYSICS need help now!!!
You have a summer job at your university’s zoology department, where you’ll be working with an animal behavior expert. She’s assigned you to study videos of different animals leaping into the air. Your task is to compare their power outputs as they jump. You&#...
Thursday, October 18, 2012 at 4:58pm

PHYSICS !!!!!!!!!!
A biophysicist grabs the ends of a DNA strand with optical tweezers and stretches it 28um . How much energy is stored in the stretched molecule if its spring constant is 0.046pN ?
Thursday, October 18, 2012 at 4:55pm

Physics
A wooden block with mass 0.26{\rm kg} rests on a horizontal table, connected to a string that hangs vertically over a friction-less pulley on the table's edge. From the other end of the string hangs a 0.20{\rm kg} mass. What minimum coefficient of static friction \mu _{{\...
Thursday, October 18, 2012 at 4:52pm

physics
A mass m = 17.0 kg is pulled along a horizontal floor with NO friction for a distance d =5.1 m. Then the mass is pulled up an incline that makes an angle è = 30.0° with the horizontal and has a coefficient of kinetic friction ìk = 0.34. The entire time the ...
Thursday, October 18, 2012 at 4:31pm

physics
A basketball player makes a jump shot. The 0.581 kg ball is released at a height of 2.02 m above the floor with a speed of 7.14 m/s. The ball goes through the net 3.10 m above the floor at a speed of 4.07 m/s. What is the work done on the ball by air resistance, a ...
Thursday, October 18, 2012 at 1:59pm

physics
a metal crate with a mass of 500 kg is pushed across a metal floor for 5 minutes.50N is applied horizontally.box does not move, extra 50 N is applied.after 2 minutes then box moves 4meters,how much work is done
Thursday, October 18, 2012 at 1:26pm

Physics
Calculate a space shuttle territory 250 km above Earth's surface. Earth's mass is 6.0 * 10^24kg and its radius is 6.38 * 10^6 m (6380km)
Thursday, October 18, 2012 at 12:57pm

Physics
A race car starts from rest on a circular track of radius 500 m. The car's speed increases at the constant rate of 0.520 m/s2. At the point where the magnitudes of the centripetal and tangential accelerations are equal, find the following. a)speed of the race car (m/s) b)...
Thursday, October 18, 2012 at 12:48pm

Physics: Rotational Motion
A 0.005kg bullet travelling horizontally with a speed of 1000m/s enters an 18kg door, embedding itself 10cm from the side opposite the hinges as in figure. The 1m wide door is free to swing on the hinges. a) Before it hits the door, does the bullet have angular momentum ...
Thursday, October 18, 2012 at 11:48am

Physics
Determine the tension in a 40 cm long pendulum when a bob of mass 200g moving at 0.7 m.s is 15 degrees from the vertical?
Thursday, October 18, 2012 at 9:50am

PHYSICS !!!!!!!!
A physicist grabs the ends of a DNA strand with optical tweezers and stretches it 28 . How much energy is stored in the stretched molecule if its spring constant is 0.046 ?
Thursday, October 18, 2012 at 2:15am

PHYSICS !!!!!!!!
A physicist grabs the ends of a DNA strand with optical tweezers and stretches it 28 . How much energy is stored in the stretched molecule if its spring constant is 0.046 ?
Thursday, October 18, 2012 at 2:07am

physics
Between each pair of vertebrae in the spinal column is a cylindrical disc of cartilage. Typically, this disc has a radius of about 2.85 10-2 m and a thickness of about 7.14 10-3 m. The shear modulus of cartilage is 1.16 107 N/m2. Suppose that a shearing force of magnitude 10 N...
Thursday, October 18, 2012 at 1:59am

physics
A flexible metal sheet of length 6.0cm, breadth 5.00cm and the average thickness of 0.883cm has a mass of 23.00g. calculate the density of the metal
Thursday, October 18, 2012 at 1:23am

physics
A 0.395-kg blue bead slides on a frictionless, curved wire, starting from rest at point in the figure below, where h = 1.50 m. At point , the blue bead collides elastically with a 0.650-kg green bead at rest. Find the maximum height the green bead rises as it moves up the wire.
Thursday, October 18, 2012 at 12:38am

Physics
Two blocks move along a linear path on a nearly frictionless air track. One block, of mass 0.107 kg, initially moves to the right at a speed of 4.70 m/s, while the second block, of mass 0.214 kg, is initially to the left of the first block and moving to the right at 6.80 m/s. ...
Thursday, October 18, 2012 at 12:08am

physics
A 23 kg chair initially at rest on a horizontal floor requires a 370 N horizontal force to set it in motion. Once the chair is in motion, a 332 N horizontal force keeps it moving at a constant velocity. The acceleration of gravity is 9.81 m/s 2 . a) What is the coe&#...
Wednesday, October 17, 2012 at 11:39pm

physics
a baseball is thrown horizontally at a velocity of 35 m/s from a height of 1.5 m. How long does it take to hit the ground? how far does it travel?
Wednesday, October 17, 2012 at 10:38pm

Physics
An arrow is shot into the air at a velocity of 25 m/s and an angle of 32 degrees above horizontal. It lands at the same level that it was shot from. How long is the arrow in air? How far does the arrow travel?
Wednesday, October 17, 2012 at 10:37pm

physics
Two forces are the only forces acting on a 2.8 kg object which moves with an accelera- tion of 2.5 m/s2 in the positive y direction. One of the forces acts in the positive x direc- tion and has a magnitude of 12 N. What is the magnitude of the other force f2? Answer in units
Wednesday, October 17, 2012 at 9:36pm

physics
A high-speed photograph of a club hitting a golf ball is shown in the figure below. The club was in contact with a ball, initially at rest, for about 0.0013 s. If the ball has a mass of 55 g and leaves the head of the club with a speed of 1.2X10^2 ft/s, find the average force ...
Wednesday, October 17, 2012 at 9:33pm

physics
A 16000 kg sailboat experiences an eastward force of 12400 N due to tide pushing its hull while the wind pushes the sails with a force of 51900 N directed toward the northwest (45 westward of North or 45 northward ofWest). What is the magnitude of the resultant ac- ...
Wednesday, October 17, 2012 at 9:17pm

physics
a .77 kg book with dimensions of 28.9 cm by 20.2 cm is on a table. What force does the book apply on the table?
Wednesday, October 17, 2012 at 8:52pm

Physics HELP!!
Three point charges have equal magnitudes, two being positive and one negative. These charges are fixed to the corners of an equilateral triangle. The magnitude of each of the charges is 3.66 μC, and the lengths of the sides of a triangle are 2.15 cm. Calculate the ...
Wednesday, October 17, 2012 at 7:50pm

Physics
A pendulum 1.70m long is released (from rest) at an angle 30 degrees. 1. Determine the speed(m/s) of the 60.0g bob at Theta = 15. 2. Determine the tension in the cord at the lowest point Theta = 0. 3. Determine the tension in the cord at Theta = 15. A formula would be ...
Wednesday, October 17, 2012 at 7:40pm

physics
convert an acceleration of 4.1 mi/h/s to m/s^2
Wednesday, October 17, 2012 at 6:52pm

physics
What will the angle of refraction be for a ray of light passing from air into a sodium chloride crystal, if the angle of incidence is 60.0°? The index of refraction of sodium chloride is 1.53.
Wednesday, October 17, 2012 at 6:35pm

physics
A certain car can accelerate from rest to the speed v in time T seconds. (a) If the power output of the car remains constant, how long does it take for the car to accelerate from v to 3v, in terms of T? (b) How fast is the car moving 9T after starting, in terms of v?
Wednesday, October 17, 2012 at 6:10pm

Physics
PLEASE SOMEONE HELP ME WITH THIS DARN QUIZ. I'm so lost and all my teachers are too 'BUSY' to help me. :/ I'm getting so sick and tired of studying and not getting it but then having to take the blame for my instructor's folly. 2. Which of the following is...
Wednesday, October 17, 2012 at 6:02pm

College Physics
13. What is the magnitude of the gravitational force that acts on two particles? Assume that particle 1 (m1) is 12 kg and particle 2 (m2) is 25 kg, they are both separated by a distance of 1.2m
Wednesday, October 17, 2012 at 5:50pm

Physics
A high-speed photograph of a club hitting a golf ball is shown in the figure below. The club was in contact with a ball, initially at rest, for about 0.0013 s. If the ball has a mass of 55 g and leaves the head of the club with a speed of 1.2 102 ft/s, find the average force ...
Wednesday, October 17, 2012 at 5:31pm

Physics URGENT!!!
A 91.0 kg fullback running east with a speed of 6.00 m/s is tackled by a 73.0 kg opponent running north with a speed of 3.00 m/s. Where did the lost energy go?
Wednesday, October 17, 2012 at 5:26pm

physics
A 1.16 kg block and a 2.32 kg block are initially at rest on a frictionless, horizontal surface, with a compressed spring of negligible mass between them. When the blocks are released, they move off in opposite directions. If the final velocity of the 1.16 kg block is 3.20 m/s...
Wednesday, October 17, 2012 at 5:22pm

Physics
1. Which of these physical situations describes an inversely proportional relationship? (Points : 1) The volume always decreases as the pressure increases. The volume always increases as the pressure increases. The pressure vs. volume graph is a straight line passing through ...
Wednesday, October 17, 2012 at 4:46pm

Physics
Four forces act on a hot-air balloon, shown from the side in the figure below. Find the magnitude and direction of the resultant force on the balloon if F1 = 5050 N, F2 = 1450 N, F3 = 950 N, and F4 = 4200 N. ________° clockwise from F2
Wednesday, October 17, 2012 at 4:34pm

physics
A 13 N force with a fixed orientation does work on a particle as the particle moves through displacement . What is the angle between the force and the displacement if the change in the particle's kinetic energy is (a) +9.19 J and (b) -9.19 J?
Wednesday, October 17, 2012 at 4:19pm

physics
a 21.2 kg mass attached to a spring scale rests on a smooth, horizontal surface. the spring scale, attached to the front end of a boxcar, reads T=35.6N when the car is in motion. If the spring scale reads zero when the car is at rest, determine the acceleration of the car, ...
Wednesday, October 17, 2012 at 4:19pm

Physics
A ball is shot from the top of a building with an initial velocity of 19m/s at an angle theta = 45 above the horizontal. Vxo and Vyo, are 13.4m/s If a nearby building is the same height and 50m away, how far below the top of the building will the ball strike the nearby ...
Wednesday, October 17, 2012 at 4:17pm

physics need help please
There are 7 charges, each with q = -5 nC distributed on a circle with radius R=3cm. The center of the circle is at the origin. The charges are at angles 0o, 45o, 90o, 135o, 180o, -90o, and -45o. (Note: A charge at -135o is missing.) a) What is the net electric field at the ...
Wednesday, October 17, 2012 at 4:14pm

physics need help please
There are 7 charges, each with q = -5 nC distributed on a circle with radius R=3cm. The center of the circle is at the origin. The charges are at angles 0o, 45o, 90o, 135o, 180o, -90o, and -45o. (Note: A charge at -135o is missing.) a) What is the net electric field at the ...
Wednesday, October 17, 2012 at 4:09pm

Physics URGENT!!!
Gayle runs at a speed of 9.00 m/s and dives on a sled, initially at rest on the top of a frictionless, snow-covered hill, that has a vertical drop of 20.0 m. After she has descended a vertical distance of 4.00 m, her brother, who is initially at rest, hops on her back, and ...
Wednesday, October 17, 2012 at 3:45pm

Physics- PLEASE HELP
A 58.0 kg soccer player jumps vertically upwards and heads the 0.45 kg ball as it is descending vertically with(b) If the ball is in contact with the players head for 19 ms, what is the average acceleration of the ball? a speed of 26.0 m/s. If the player was moving upward with...
Wednesday, October 17, 2012 at 3:43pm

Physics. Help please
A small permanent magnet is located on the x-axis with the center at <15,0,0>cm. The magnet’s North pole is at location <14.5, 0, 0>cm and the South pole is at location <15.5, 0, 0>cm. A current loop is placed in the y-z plane, such that its center is ...
Wednesday, October 17, 2012 at 3:40pm

PHYSICS
A long-straight wire carries a current and is aligned with the North-South direction. You place a compass 4 cm directly above the wire and above the North/East/South/West plane. The compass needle, which initially pointed North (far away from the wire) is now deflected by 20o ...
Wednesday, October 17, 2012 at 3:36pm

physics
If a seagull flies to a height of 22.5 meters, how long will the clam take to fall? The acceleration of gravity is 9.8m/s. answer in units of sec
Wednesday, October 17, 2012 at 3:35pm

Physics
A boat’s speed in still water is 1.95m/s . The boat is to travel directly across a river whose current has speed 1.20m/s . Determine the speed of the boat with respect to the shore. Despite, I did it like taking the sqrt (1.95^2+1.20^2) is there something wrong I did? ...
Wednesday, October 17, 2012 at 3:13pm

physics
A solid ball rolls along a frictionless plane. It is 4 kilograms and is moving at a velocity of 15 meters per second. If it has a completely elastic collision and transfers all of its momentum to a stationary solid ball of 14 kilograms, what will be the velocity of the second ...
Wednesday, October 17, 2012 at 2:17pm

Physics
A block of mass 3m is placed on a frictionless horizontal surface, and a second block of mass m is placed on top of the first block. The surfaces of the blocks are rough. A constant force of magnitude F is applied to the first block as shown in the figure. (a) Construct free-...
Wednesday, October 17, 2012 at 2:07pm

Physics IB
Two billiard balls of equal mass undergo a perfectly elastic head-on collision. If the speed of ball 1 was initially 5.00 m/s, and that of ball 2 was 7.00 m/s in the opposite direction, what will be their speeds after the collision? I figured out how to calculate the velocity ...
Wednesday, October 17, 2012 at 1:45pm

physics
what is the particle's average velocity in the y direction vy between t=0.200s and t=0.300s?
Wednesday, October 17, 2012 at 1:30pm

Physics
Ann, a 66.1 kg person throws a 0.0460 kg snowball forward with a ground speed of 31.7 m/s. Billy, with a mass of 60.5 kg, catches the snowball. Both people are on skates. Ann is initially moving forward with a speed of 2.29 m/s, and Billy is initially at rest. After the ...
Wednesday, October 17, 2012 at 12:54pm

Physics
A man claims he can safely hold on to a 12.80 kg child in a head-on collision with a relative speed of 133. mi/h lasting for 0.100 s as long as he has his seat belt on. (a) Find the magnitude of the average force needed to hold onto the child.
Wednesday, October 17, 2012 at 12:53pm

Physics
Standing at the edge of a cliff 240 m tall, you throw two balls into the air – one directly upwards at 5 m/s and another directly downwards at -5 m/s. Use conservation of energy to show that they will have the same final speed at the bottom.
Wednesday, October 17, 2012 at 12:30pm

physics
A discus thrower (with arm length of 1.2 m) starts from rest and begins to rotate counterclockwise with an angular acceleration of 1.8 rad/s2. (a) How long does it take the discus thrower's speed to get to 3.4 rad/s? (b) How many revolutions does the thrower make to reach ...
Wednesday, October 17, 2012 at 12:01pm

PHYSICS ASAP!
A Football is kicked 66.6 meters in 5.39 seconds. What was the initial velocity? Magnitude and Direction
Wednesday, October 17, 2012 at 11:58am

Physics- PLEASE HELP
A 58.0 kg soccer player jumps vertically upwards and heads the 0.45 kg ball as it is descending vertically with(b) If the ball is in contact with the players head for 19 ms, what is the average acceleration of the ball? a speed of 26.0 m/s. If the player was moving upward with...
Wednesday, October 17, 2012 at 11:43am

Physics
Roller Coaster Cart Mass = 200kg String Compressed by 5m Initial Velocity 25 m/s PE = 2,500 J KE = 62,500 J Use the law of conservation of mechanical energy to find the maximum radius the loop can have before the cart falls off
Wednesday, October 17, 2012 at 11:33am

Physics
1. The mass of Kerry and the sledge together is 40 kg. Sam pushes with a force of 50 N for 4 s. a. What is the value of the quantity: (force x time) during which the force acts? 50 x 4 = 200 b. So what is the increased momentum of Kerry and the sledge? c. What speed does Sam ...
Wednesday, October 17, 2012 at 11:14am

Physics URGENT!!!
A 75.0 kg fullback running east with a speed of 6.00 m/s is tackled by a 82.0 kg opponent running north with a speed of 5.00 m/s. (a) Calculate the velocity of the players immediately after the tackle. (b)Calculate the direction of the players immediately after the tackle.(c)...
Wednesday, October 17, 2012 at 11:03am

physics
A football is kicked 66.6 meters. If the ball is in the air for 5.39 seconds, with what initial velocity was it kicked?
Wednesday, October 17, 2012 at 10:55am

Physics
Roller Coaster Cart Mass = 200kg String Compressed by 5m Initial Velocity 25 m/s Find the Spring Constant
Wednesday, October 17, 2012 at 10:50am

Physics
A crank of length 190mm is initially at 65 degree above the horizontal, and rotates through 35 degree towards the horizontal. A vertically downward force of 160 N acts on the outer end of the crank. Calculate the work done by the force.
Wednesday, October 17, 2012 at 10:15am

Physics
HI! :( Im sorry to bother you guys but I need help on only these three questions. I'm not trying to cheat but these three are really confusing. This is the first time I've ever asked for help on the internet haha. Please dont be upset I promise this is the only time. ...
Wednesday, October 17, 2012 at 6:49am

Physics
PLEASE HELP, I'm trying to study for a quiz >.< and I don't understand this one question! A fellow student reports his measurements of time for a speed calculation in minutes. How could he express that calculation using SI base units? A)convert minutes to hours ...
Wednesday, October 17, 2012 at 6:30am

Physics
How many newtons of force are necessary to accelerate a 0.0050 kg mass at the acceleration (a) of 9.81 m/s2 with the force expressed in the correct number of significant figures? (F = ma) 0.04905 N 0.049 N 0.05 N 4.91 × 102 N Please help me :( It's just one little ...
Wednesday, October 17, 2012 at 5:55am

PHYSICS!!!!!!!!!!!!!!!!
the height from where the water bomb will be released on the overpass is 4.5 m and the target student is 170 cm tall. the student realises that, as his target will be moving, he must release the water bomb when his friend is a certain horizontal distance from the point of ...
Wednesday, October 17, 2012 at 2:53am

Physics
An amusement park ride consists of a rotating circular platform 8.00 m in diameter from which 9.5 kg seats are suspended at the end of 2.50 m massless chains. When the system rotates, the chains make an angle θ = 31.0° with the vertical. Assume the average mass of a ...
Wednesday, October 17, 2012 at 1:47am

physics
The shock absorbers in the suspension system of a car are in such bad shape that they have no effect on the behavior of the springs attached to the axles. Each of the identical springs attached to the front axle supports 294 kg. A person pushes down on the middle of the front ...
Wednesday, October 17, 2012 at 1:44am

physics
A particular trophy has a solid 0.2m radius base with a mass of 1.2kg. Rising up from the center is a 0.01m radius solid rod with a mass of 0.4kg. Centered on top of this is a hollow sphere with a radius of 0.15m and a mass of 0.8kg. Calculate the total moment of inertia for ...
Tuesday, October 16, 2012 at 11:41pm

Physics HELP!!
Three charges, q1=+45.9nC q2=+45.9nC and q3=+91.8nC are fixed at the corners of an equilateral triangle with a side length of 3.70cm. Find the magnitude of the electric force on q3.
Tuesday, October 16, 2012 at 11:05pm

physics
Salmon often jump waterfalls to reach their breeding grounds. Starting 3.16 m from a waterfall 0.257 m in height, at what minimum speed must a salmon jumping at an angle of 37.9◦ leave the water to continue upstream? The acceleration due to gravity is 9.81 m/s2 . Answer ...
Tuesday, October 16, 2012 at 10:04pm

physics
A block is released from rest at the top of an incline which makes a 30 degree angle with the horizontal. The incline is 12 m long and it takes the block 25 seconds to reach the bottom. What is the coefficient of kinetic friction, between the block and the incline?
Tuesday, October 16, 2012 at 9:46pm

Honors Physics
A plane traveling at 300.0 km/h attempts to land on a 500 m runway. The plane’s engines and brakes accelerate uniformly at –5.0 m/s2. Will the plane be able to land safely?
Tuesday, October 16, 2012 at 8:56pm

Physics
A block (weight= 10kg) is sitting on a surface with friction (coefficient= 0.5). A force (push) is applied to the end of the block, 35 degrees below the horizontal. Calculate the magnitude of the force to move the block.
Tuesday, October 16, 2012 at 8:47pm

Physics
A block of 1.0 kg rests on the gap between two boards. Putty is throw from the underside of the block and makes contact with it. The Putty has a velocity of 15 m/s and weighs 0.3kg. Calculate the max height the block travels after contact with the putty, assuming they stick ...
Tuesday, October 16, 2012 at 8:43pm

Physics
Two blocks rest on two frictionless ramps. They are connected at the apex of each ramp by a string and pulley. The angle of ramp A with the ground is 45 degrees. Mass of Block B (on Ramp B) is 2 times that of Block A. What does the angle of Ramp B with the ground have to be in...
Tuesday, October 16, 2012 at 8:37pm

Physics
Two carts of identical mass (500 kg). One is traveling south and the other is traveling east. They collide (inelastic collision) and slide 3 meters, 30 degrees south of the east. The total friction force is 10,000N. Calculate the initial velocities of each.
Tuesday, October 16, 2012 at 8:33pm

physics
The current-density magnitude in a certain circular wire is J = (2.75 × 10 10 ⁄ )r 2 , where r is the radial distance out to the wire’s radius of 3.00 mm. The potential applied to the wire (end to end) is 60.0 V. How much energy is converted to thermal energy ...
Tuesday, October 16, 2012 at 8:10pm

physics
a marble dropped from rest falls freely until it hits the ground with a speed of 35 meters per second. the time during which the marble is in free fall is approximately
Tuesday, October 16, 2012 at 7:02pm

physics
a teniss ball thrown vertically upward reaches a maximun height of 33 meters above the surface of earth. at its maximun height the speed of he tennis ball is
Tuesday, October 16, 2012 at 7:00pm

physics
An eagle (m1 = 5.2 kg) moving with speed v1 = 6 m/s collides with a second eagle (m2 = 4.8 kg) moving with speed v2 = 5.6 m/s in a direction at right angle to the first one. After the collision, they hold onto one another. With what speed are they moving after the collision
Tuesday, October 16, 2012 at 6:38pm

Physics
An asteroid with mass m = 1.85*10^9 kg comes from deep space, effectively from infinity, and falls toward Earth. How much work would have to be done on the asteroid by friction to slow it to 550 m/s by the time it reached a distance of 1.50*10^8 m from Earth?
Tuesday, October 16, 2012 at 6:34pm

Physics
A car travels in a flat circle of radius R. At a certain instant the velocity of the car is 24 m/s west,and the acceleration of the car has componets of 2.4 m/s^2 east and 1.8m/s^2 south. Find the total displacement of the object (from t=0 to 25)
Tuesday, October 16, 2012 at 5:58pm

physics...PLZ HELP! =)
A constant force acts on a moving object. The object makes a fixed magnitude of displacement in some direction. In general, in what direction is the displacement that will result in the object traveling with the least kinetic energy after the displacement occurs? A.The same ...
Tuesday, October 16, 2012 at 5:45pm

physics..help PLZ!!
An object undergoes a displacement while being acted on by a constant force directed to the north. The work done on this object by the force is positive during the displacement. Which statement is necessarily true about the average velocity of the object during the ...
Tuesday, October 16, 2012 at 5:42pm

physics
In a Broadway performance, an 80 kg actor swings from a 3.75 m long cable that is horizontal when he starts.? At the bottom of his arc, he picks up his 55.0 kg costar in an inelastic collision. What maximum height do they reach after their upward swing?
Tuesday, October 16, 2012 at 4:29pm

Physics- Elena please help!
A 20.0 g bullet is fired horizontally into a 85 g wooden block that is initially at rest on a frictionless horizontal surface and connected to a spring having spring constant 156 N/m. The bullet becomes embedded in the block. The bullet block system compresses the spring by a ...
Tuesday, October 16, 2012 at 4:16pm

Physics
Which of the following is not a good example of uniform circular motion? a) a person riding on a ferris wheel that is turning at a constant rate b) a person taking off on an airplane to fly around the world on a path defined by the equator c) a race car driving at a constant ...
Tuesday, October 16, 2012 at 4:15pm

Physics
Four forces act on a hot-air balloon, shown from the side in the figure below. Find the magnitude and direction of the resultant force on the balloon if F1 = 5050 N, F2 = 1450 N, F3 = 950 N, and F4 = 4200 N. _______ N at ________ ° clockwise from F2
Tuesday, October 16, 2012 at 4:12pm

Physics
A package of dishes (mass 50.0 kg) sits on the flatbed of a pickup truck with an open tailgate. The coefficient of static friction between the package and the truck's flatbed is 0.330, and the coefficient of kinetic friction is 0.230. (a) The truck accelerates forward on ...
Tuesday, October 16, 2012 at 3:50pm

Physics.
A block of mass 3m is placed on a frictionless horizontal surface, and a second block of mass m is placed on top of the first block. The surfaces of the blocks are rough. A constant force of magnitude F is applied to the first block. a) Identify the horizontal force that ...
Tuesday, October 16, 2012 at 3:17pm

Physics
You are pulling a 60-kg crate across a level floor with a rope. If a force of 200 N on the rope gives the crate an acceleration of 2 m/s2, what is the force of friction that the crate exerts on the floor?
Tuesday, October 16, 2012 at 3:11pm

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