a boat weights 10,000 newtons what is the magnitude of buoyant force acting on boat in the fliud
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science
a boat weights 10,000 newtons what is the magnitude of buoyant force acting on boat in the fliud 
Physics
A 214 Kg boat is sinkin in the ocean. The boat has a weight of 2100 N. The boat's weight is partially offset by the 790 N buoyant force of the water acting upward. What is the net acceleration of the boat 
Physics
A 1250 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the frictional force fk between boat and water is proportional to the speed v of the boat. Thus, fk = 80v, where v is in meters per second and fk (the magnitude of the frictional force) is in ... 
Physics
A 1250 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the frictional force fk between boat and water is proportional to the speed v of the boat. Thus, fk = 80v, where v is in meters per second and fk (the magnitude of the frictional force) is in ... 
Physics
A 1250 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the frictional force fk between boat and water is proportional to the speed v of the boat. Thus, fk = 80v, where v is in meters per second and fk (the magnitude of the frictional force) is in ... 
college physics
A fisherman poles a boat as he searches for his next catch. He pushes parallel to the length of the light pole, exerting a force of 245 on the bottom of a shallow lake. The pole lies in the vertical plane containing the boat's keel. At one moment, the pole makes an angle of 34... 
Physics
A 9000 Kiogram boat floats in a lake. If half of the boat is submerged, which of the following is true: 1. The boat is less dense than the water in the lake. 2. The buoyant force is less than half the weight of the boat. 3. The buoyant force is greater than the total weight of... 
physics
A 1000 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the kinetic frictional force f_k between the boat and water is proportional to the speed v of the boat: f_k = 70v, where v is in meters per second and f_k is in newtons. Find the time required... 
Physics
A boat is constructed in the shape of a rectangular cube. The base of the boat is 2m by 3m and the side of the boat is 2m high. The boat has a total mass of 4500kg. HintThe density of the water is 1000kg/m^3. a. What is the buoyant force on the boat? Explain answer. b. ... 
physics
A 214 kg boat is sinking in the ocean. The boat's weight is partially offset by the 790 N buoyant force of the water. What is the net acceleration of the boat? 
Physics
A person, sunbathing on a warm day, is lying horizontally on the deck of a boat. Her mass is 59.6 kg, and the coefficient of static friction between the deck and her is 0.696. Assume that she is moving horizontally, and that the static frictional force is the only force acting... 
Physics  Friction
**Especially part a) A person, sunbathing on a warm day, is lying horizontally on the deck of a boat. Her mass is 54.6 kg, and the coefficient of static friction between the deck and her is 0.683. Assume that she is moving horizontally, and that the static frictional force is ... 
physics
The loadbearing piston in a certain hydraulic system has an area 20 times as large as the input piston. If the larger piston supports a load of 2000N, how large a force must be applied to the input piston? A certain boat displaces a volume of 4.5m3 of water (the density of ... 
Physics
A boat weighing 9.0 × 10 2 newtons requires a horizontal force of 6.0 × 10 2 newtons to move it across the water at 1.5 × 10 1 meters per second. The boat’s engine must provide energy at the rate of 
Physics
A tugboat pulls a ship with a constant horizontal force of 6000N and causes the ship to move through a harbor. The water exerts a constant drag force on the ship of 500N. How much work is done on the ship if it moves a distance of 4.0 km? Force is causing parallel displacement... 
physics
If a boat is being tugged by 2 tug boats 20000 newtons north, the river is flowing at 5000 newtons south what direction is the boat and what's the velocity? 
Physics
A power boat of mass 495 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 780 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assumecontrary to factthat the resistive force due to the water is constant, ... 
Physics
A power boat of mass 460 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 765 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assumecontrary to factthat the resistive force due to the water is constant, ... 
physics
A power boat of mass 465 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 765 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assumecontrary to factthat the resistive force due to the water is constant, ... 
physics
Two people are pulling a boat through the water as in the figure below. Each exerts a force of 600 N directed at a è = 20.0° angle relative to the forward motion of the boat. If the boat moves with constant velocity, find the resistive force exerted by the water on the boat. 
physics
Two people are pulling a boat through the water as in the figure below. Each exerts a force of 600 N directed at a è = 45.0° angle relative to the forward motion of the boat. If the boat moves with constant velocity, find the resistive force exerted by the water on the boat. 
physics
(Densities of object 1 and 2 are greater than that of the fluid) 1. Object 1 and 2 have same volume and shape, but object 1 is more dense than object 2, which one has greater buoyant force?? 2. object 1 and 2 has same mass, but density of object 1 is greater than object 2(has ... 
cpcc
Two people are pulling a boat through the water as in Figure P4.20. Each exerts a force of 600 N directed at a θ = 45.0° angle relative to the forward motion of the boat. If the boat moves with constant velocity, find the resistive force vector F exerted by the water on ... 
Physics
Could someone help me with this, please. Thanks. The tension in a rope attached to a boat is 27.5 lb. The rope is attached to the boat 6.0 ft below the level at which the boat is being drawn in. At the point where there is 18.0 ft of rope out, what force is bringing the boat ... 
Physics
Can someone help me with this problem? It requires a lot of visualizing and I've never been great at problems like that. A pair of blocks of mass m1 =29.0 kg, and m2 =58.0 kg, are being pushed on a horizontal surface by a constant forces of magnitude F=87.0 N. The angle θ... 
Physics
The tension in a rope attached to a boat is 27.5 lb. The rope is attached to the boat 6.0 ft below the level at which the boat is being drawn in. At the point where there is 18.0 ft of rope out, what force is bringing the boat towards the dock, and what force tends to raise ... 
physics
A boat moves through the water with two forces acting on it. One is a 2100. N forward push by the water on the propeller, and the other is a 1600. N resistive force due to the water around the bow. (a) What is the acceleration of the 1200. kg boat? (b) If it starts from rest, ... 
physics
Two people pull as hard as they can on ropes attached to a 170 kg boat. If they pull in the same direction, the boat has an acceleration of 1.59 m/s2 to the right. If they pull in opposite directions, the boat has an acceleration of 0.518 m/s2 to the left. What is the force ... 
Physics  URGENT
Four forces are acting on an object in static equilibrium: Force 1 has a magnitude of 46.0 N and is acting at an angle of 52 degrees above the positive xaxis. Force 2 has a magnitude of 29 N and is acting along the positive xaxis. Force 3 has a magnitude of 34.5 N and is ... 
physics
Four forces are acting on an object in static equilibrium: Force 1 has a magnitude of 46.0 N and is acting at an angle of (54) degrees above the positive xaxis. Force 2 has a magnitude of (42) N and is acting along the positive xaxis. Force 3 has a magnitude of 34.5 N and is... 
physics
Two people pull as hard as they can on ropes attached to a 200 kg boat. If they pull in the same direction, the boat has an acceleration of 1.44 m/s2 to the right. If they pull in opposite directions, the boat has an acceleration of 0.518 m/s2 to the left. What is the force ... 
Physics
Two people pull as hard as they can on ropes attached to a boat of mass 200 kg. If they pull in the same direction, the boat has an acceleration of 4 m/s^2. what is the force exerted by each person on the boat? Disregard any other forces on the boat. 
physics
SOMEBODY ANSWER THIS PLEASE, Two people pull as hard as they can on ropes attached to a 170 kg boat. If they pull in the same direction, the boat has an acceleration of 1.59 m/s2 to the right. If they pull in opposite directions, the boat has an acceleration of 0.518 m/s2 to ... 
Physics
A boat is pulled through a canal by horses walking parallel to the canal and exerting a force of 1000 N on a tow rope 40 meters long. If the distance from the boat to the horse track is 15 meters, what is the magnitude of the effective component pulling the boat forward? 
physics
A power boat of mass 460 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 765 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assume  contrary to fact  that the resistive force due to the water is ... 
physics
A boat heads directly across a river 39 m wide at 3.9 m/s. The current is flowing downstream at 2.4 m/s. (a) What is the resultant velocity of the boat? m/s (magnitude) ° (direction) (b) How much time does it take the boat to cross the river? s (c) How far downstream is the ... 
12th grade physics
A boat pulled through a canal by horses walking parallel to the canal and exerting a force of 1000 N on a tow Rope 40 meters long. Is the distance from the boat to the horse track is 15 meters, what is the magnitude of the effective component pulling the boat forward 
Physicsforces
1. Harry is pushing a car down a level road at 2.0m/s with a force of 243N. The total force acting on the car in the opposite direction, including road friction and air resistance, is which of the following? a) slightly more than 243N b) exactly equal to 243N c) slightly less ... 
Physics
As two boats approach the marina, the velocity of boat 1 relative to boat 2 is 2.29 m/s in a direction 37.8° east of north. If boat 1 has a velocity that is 0.745 m/s due north, what is the magnitude of the velocity of boat 2? 
Physics
A power boat of mass 475 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 770 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assume  contrary to fact  that the resistive force due to the water is ... 
Physics
As two boats approach the marina, the velocity of boat 1 relative to boat 2 is 2.20m/s in a direction 47.0 ∘ East of North. If boat 1 has a velocity that is 0.745m/s due North, what is the(magnitude and direction) of boat 2? 
physics
A boat moves through the water with two forces acting on it. One is a 2.32×10^3 N forward push by the motor, and the other is a1.79×10^3 N resistive force due to the water.What is the acceleration of the 1279.5 kg boat? 
physics
A 240kg boat is at rest in calm conditions. A sudden wind pushes the boat 200 meters in 30 seconds. What was the net force on the boat if the acceleration was constant? 
phy
A boat can travel 2.60 m/s in still water.If the boat points its prow directly across a stream whose current is 1.10 m/s, what is the velocity (magnitude and direction) of the boat relative to the shore? What will be the position of the boat, relative to its point of origin, ... 
Physics
What force is must a jet's boat engine apply to accelerate the boat from 50 km/h to 100 km/h in 6.0 s? The mass of the boat is 800 kg and the coefficient of kinetic friction is 0.30. I found acceleration by doing v2v1 / t, but im not sure what to do next? 
physics
As two boats approach the marina, the velocity of boat 1 relative to boat 2 is 2.20m/s in a direction 47.0 ∘ east of north. If boat 1 has a velocity that is 0.745m/s due north, what is the velocity (magnitude and direction) of boat 2? 
Trigonometry
1. Ben is pulling on a tobaggan rope with a force of 250 newtons. The rope makes a 36 angle with the ground. What force is actually working to move the tobaggan to the right? 2. If a boat going 6 mi/hr in still water suddenly encounters a crosscurrent of 4 mi/hr, at what angle... 
physics
A boat is traveling upstream in the positive direction of an x axis at 14 km/h with respect to the water of a river. The water is flowing at 9.0 km/h with respect to the ground (parallel to the boat). What are the (a) magnitude and (b) direction of the boat’s velocity with ... 
Science
A child in a boat throws a 5.30 kg package out horizontally with a speed of 10 m/s, see the figure. Calculate the velocity of the boat immediately after, assuming it was initially at rest. The mass of the child is 26.0 kg and that of the boat is 55.0 kg What is the magnitude? 
physics
a boat heads directly across a river with a speed through the water 8m/s. the river current is 2m/s a. what is the magnitude and direction of the boat velocity relative to the earth? b.when the boat reaches the other bank, how far will it be? 
physics
A 1.54 ×104 N boat experiences a force of 2 000 N from east by the ocean tide and a wind force against its sails with magnitude of 4000 N directed toward the northwest (60° N of W). Find the magnitude and the direction of the resultant acceleration 
Physics
A 343kg boat is sailing 16.2° north of east at a speed of 1.98 m/s. Thirty seconds later, it is sailing 37.5° north of east at a speed of 3.76 m/s. During this time, three forces act on the boat: a 30.3N force directed 16.2° north of east (due to an auxiliary engine), a ... 
physics
A child in a boat throws a 6.00 kg package out horizontally with a speed of 12.0 m/s, Fig. 728. Calculate the velocity of the boat immediately after, assuming it was initially at rest. The mass of the child is 25.0 kg and that of the boat is 50.0 kg. Magnitude ___m/sDirection 
physics
Two boats start together and race across a 42 km wide lake and back. Boat A goes across at 42 km/h and returns at 42 km/h. Boat B goes across at 21 km/h, and its crew, realizing how far behind it is getting, returns at 63 km/h. Turnaround times are negligible, and the boat ... 
physics
Two boats start together and race across a 42 km wide lake and back. Boat A goes across at 42 km/h and returns at 42 km/h. Boat B goes across at 21 km/h, and its crew, realizing how far behind it is getting, returns at 63 km/h. Turnaround times are negligible, and the boat ... 
physics
Two boats start together and race across a 42 km wide lake and back. Boat A goes across at 42 km/h and returns at 42 km/h. Boat B goes across at 21 km/h, and its crew, realizing how far behind it is getting, returns at 63 km/h. Turnaround times are negligible, and the boat ... 
physics
A boat moves through the water with two forces acting on it. One is a 2000 N forward push by the motor on the propeller, and the other is an 1741 N resistive force due to the water around the bow. What is the acceleration of the 1020 kg boat? Answer in units of m/s2 
Physics
A boat moves through the water with two forces acting on it. One is a 2304N forward push by the motor on the propeller, and the other is a 2154N resistive force due to the water around the bow. What is the acceleration of the 1293kg boat? Answer in units of m/s^2. 
physics
A boat moves through the water with two forces acting on it. One is a 2123 N forward push by the motor on the propeller, and the other is an 1930 N resistive force due to the water around the bow. What is the acceleration of the 1345 Kg boat? Answer in units of m/s^2 
physics
Two boats start together and race across a 42 km wide lake and back. Boat A goes across at 42 km/h and returns at 42 km/h. Boat B goes across at 21 km/h, and its crew, realizing how far behind it is getting, returns at 63 km/h. Turnaround times are negligible, and the boat ... 
Algebra
A boat was purchased for $45,000. Assuming the boat depreciates at a rate of $4700 per year (straightline depreciation) for the first 8 years, write the value v of the boat as a function of the time t (measured in years) for 0 ¡Ü t ¡Ü 8. v(t) = _______ , 0 ¡Ü t ¡Ü 8 
algebra
A boat was purchased for $45,000. Assuming the boat depreciates at a rate of $4700 per year (straightline depreciation) for the first 8 years, write the value v of the boat as a function of the time t (measured in years) for 0 ¡Ü t ¡Ü 8. v(t) = ____, 0 ¡Ü t ¡Ü 8 
Physics
A boat is headed due east (0) at 20 km/hr. A wind blowing to the south west at 18 km/hr is also acting upon it. What is the boat's velocity? 
Physics
A boat moves through the water with two forces acting on it. One is a 1500 N forward push by the motor, and the other is an 1400 N resistive force due to the water. (a) What is the acceleration of the 1100 kg boat? m/s 2 (b) If it starts from rest, how far will it move in 7.0 ... 
physics
a boat of mass 90 kg is floating in still water a body of mass 30 kg walks from the stern to the boat the length of the boat is 3m. calculate the distance through which the boat move. 
Physics
A boat has a mass of 6800 kg. Its engines generate a drive force of 4500 N, due west, while the wind exerts a force of 660 N, due east, and the water exerts a resistive force of 1200 N due east. What is the magnitude and direction of the boat's acceleration? 
physics
A motorboat travels due north at a steady speed of 3.0 m/s through calm water in which there is no current. The boat then enters an area of water in which a steady current flows at 2.0 m/s in a southwest direction, as shown in the next picture. Both the engine power and the ... 
AP PHYSICS
A speedboat starts from rest and accelerates at +2.01 m/s2 for 7.15 s. At the end of this time, the boat continues for an additional 6.25 s with an acceleration of +0.518 m/s2. Following this, the boat accelerates at 1.49 m/s2 for 8.55 s. (a) What is the velocity of the boat ... 
Physics
A speedboat starts from rest and accelerates at +2.01 m/s2 for 7.05 s. At the end of this time, the boat continues for an additional 6.15 s with an acceleration of +0.518 m/s2. Following this, the boat accelerates at 1.49 m/s2 for 8.50 s. (a) What is the velocity of the boat ... 
Physics
A speedboat starts from rest and accelerates at +1.98 m/s2 for 8.25 s. At the end of this time, the boat continues for an additional 5.58 s with an acceleration of +0.348 m/s2. Following this, the boat accelerates at 1.42 m/s2 for 7.22 s. (a) What is the velocity of the boat ... 
physics
A speedboat starts from rest and accelerates at +1.69 m/s2 for 7.18 s. At the end of this time, the boat continues for an additional 4.55 s with an acceleration of +0.468 m/s2. Following this, the boat accelerates at 0.657 m/s2 for 8.38 s. (a) What is the velocity of the boat... 
physics
A speedboat starts from rest and accelerates at +1.69 m/s2 for 7.18 s. At the end of this time, the boat continues for an additional 4.55 s with an acceleration of +0.468 m/s2. Following this, the boat accelerates at 0.657 m/s2 for 8.38 s. (a) What is the velocity of the boat... 
physics
A speedboat starts from rest and accelerates at +1.68 m/s2 for 5.43 s. At the end of this time, the boat continues for an additional 8.16 s with an acceleration of +0.475 m/s2. Following this, the boat accelerates at 0.866 m/s2 for 7.54 s. (a) What is the velocity of the boat... 
physics
A bookshelf is at rest in a room. A force of 35.0 newtons is applied to a bookshelf. If the floor imparts a frictional force of 2.90 newtons, what is the net force acting on the bookshelf? 37.9 newtons 32.1 newtons 33.1 newtons 35.0 newtons 50.5 newtons 
Physics
The record number of boat lifts, including the boat and its ten crew members was achieved by Sami Heinonen and Juha Räsänen of Sweden in 2000. They lifted a total mass of 653.2 kg approximately 4 in. off the ground a total of 24 times. Estimate the total mechanical work done... 
Physics
A boat crosses a river of width 113 m in which the current has a uniform speed of 0.933 m/s. The pilot maintains a bearing (i.e., the direction in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 2.58 m/s relative to the ... 
physics
A car is towing a boat on a trailer. The driver starts from rest and accelerates to a velocity of +11.4 m/s in a time of 29.2 s. The combined mass of the boat and trailer is 443 kg. The frictional force acting on the trailer can be ignored. What is the tension in the hitch ... 
Physics
A boat sets off perpendicular to the bank, to cross a river width of 250m. The speed of the boat in still water is 3.20ms1, however there is a current downstream at 1.20ms1, which puss the boat sideways. a) Find the resultant velocity of the boat. b) Find the total distance ... 
physics
A boat moves through the water with two forces acting on it. One is a 2.05 103 N forward push by a motor, and the other is a 1.75 103 N resistive force due to the water. (a) What is the acceleration of the 1080 kg boat? (b) If it starts from rest, how far will it move in 9 s... 
Physics
An empty rubber balloon has a mass of 0.012kg. the balloon is filled with helium at 0 degrees celcius, 1 atm pressure, and a density of 0.179 kg/m3. the filled balloon has a radius of 0.5 m. a)what is the magnitude of the buoyant force acting on the balloon? b)what is the ... 
physics
An 800 kg police boat slows down uniformly from 50 km/h [E] to 20 km/h [E] as it enters a harbour. If the boat slows down over a 30 m distance, what is the force of friction on the boat? (Hint: You will need to convert the velocities into m/s.) 
Physics
An empty rubber balloon has a mass of 0.0120 kg. The balloon is filled with helium at 0 degrees celsuis, 1 atm pressure, and a density of 0.179kg/m^3. The filled balloon has a radius of .5m a)What is the magnitude of the net force acting on the balloon? b) What is the ... 
math
A woman is sitting in a boat at anchor on a lake. Her boat bobs up and down once every 2.0·s. She notices that when the front of her 3.0·m long boat is at one wave crest, a second crest is at the middle of her boat, and a third is at the end. What is the frequency of the waves? 
Physics
A woman is sitting in a boat at anchor on a lake. Her boat bobs up and down once every 2.0·s. She notices that when the front of her 5.0·m long boat is at one wave crest, a second crest is at the middle of her boat, and a third is at the end. What is the frequency of the waves? 
Physics
A boat moves through the water with two forces acting on it. One is a 2.06 103 N forward push by a motor, and the other is a 1.75 103 N resistive force due to the water. a)What is the acceleration of the 1300 kg boat? b)If it starts from rest, how far will it move in 11 s? c)... 
physics
A boat of mass 120 kg floats in a stream. You push on the boat with a pole, exerting a force of (175 i hat  145 j hat) N. The boat moves through a displacement dvec = (23.0 i hat  8.0 j hat) m along a straight line. 
calculus
Boat A leaves the dock at 12pm heading due South at a constant speed of 20 km/h. Meanwhile, at 12pm Boat B, a pirate ship, is 15 km due West of the dock where boat A started, and is sailing due East at a constant speed of 15 km/h. If the pirates get within 10 km of another ... 
Physics
A boat is traveling upstream at 13 km/h with respect to the water of a river. The water is flowing at 9.0 km/h with respect to the ground. What are the (a) magnitude and (b) direction of the boat’s velocity with respect to the ground? A child on the boat walks from front to ... 
physics
A 70kg fisherman in a 138kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.8 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ... 
physics
A 70kg fisherman in a 138kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.8 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ... 
physics
A 74kg fisherman in a 129kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.7 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ... 
physcis
Boat A negotiates a curve whose radius is 375 m. Boat B negotiates a curve whose radius is 150 m. Each boat experiences the same centripetal acceleration. What is the ratio of the speed of boat A to that of boat B? 
physics
Boat A negotiates a curve whose radius is 336 m. Boat B negotiates a curve whose radius is 160 m. Each boat experiences the same centripetal acceleration. What is the ratio of the speed of boat A to that of boat B? 
Math (Calculus)
At 2:00 pm boat K is 25 km north of boat L. If boat K is sailing 5 km/h west and boat L is sailing north at 20 km/h, what is the rate at which the distance between the two boats in changing at 2:30? 
physic
the speed boat has a acceleration of 2.0 m/s2 if the initial velocity of the boat is 6.0 m/s2. find the boat displacement after 8.0 seconds? 
physics
Ms. Muse shoots a 0.005 toy dart at a toy boat with a plastic sail. The dart sticks to the sail of the boat and begins to move in the opposite direction. What is the final velocity of the boat if the boat was originally traveling toward Ms. Muse at 0.05 m/s, the mass of the ... 
Physics
A boat crosses a river of width 122 m in which the current has a uniform speed of 2.39 m/s. The pilot maintains a bearing (i.e., the direction in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 2.81 m/s relative to the water... 
Physics
A boat crosses a river of width 115 m in which the current has a uniform speed of 1.84 m/s. The pilot maintains a bearing (i.e., the direction in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 1.1 m/s relative to the water... 
physics
A man is in a boat out away from shore. Th mass of the man, the boat and everything in it is 210 kg. The boat is not moving. The man throws and anchor with a mass of 26 kg straight out from the boat with a speed of 6.6 m/s. What is the resulting speed of the boat? 
Physics
A speed boat at rest begins to move in a straight line from a dock. The boat has a constant acceleration of +3.0 m/s squared. Attached to the dock is a siren that is producing a 755 Hz tone. If the air temperature is 20 degrees C, what is the frequency of the sound heard by a ...