Boat Definition and 366 Threads

Homework Statement A man with mass m1 = 55 kg stands at the left end of a uniform boat with mass m2 = 175 kg and a length L = 2.7 m. Let the origin of our coordinate system be the man’s original location as shown in the drawing. Assume there is no friction or drag between the boat and water...

Homework Statement A fisherman wishes to cross a river to the shore directly south of his position. The river is 400 m across, and the fisherman's boat is capable of a speed of 2.5m/s. If the river's current has a velocity of 1.5m/s [W], determine a) the time it takes the fisherman to cross...

Homework Statement A river flows due north with a speed of 2.90 m/s. A man rows a boat and reaches the opposite shore right across its initial position; his velocity relative to the water is 5.50m/s. His landing point is due east relative to its initial location. The river is 1000 m wide. a)...

Homework Statement Boat is moving at a speed of 6 m/s Boat now accelerates at 3 m/s until it reaches a speed 12 m/sHomework Equations What is the distance traveled by the boat during this acceleration?

Homework Statement The carbon in living matter contains fixed proportion of the radioactive isotope carbon-14. The carbon-14 in 1.00g of living matter has an activity of 0.250Bq. The half life of carbon-14 is 5730 years. (a) Calculate (i) The decay constant in s-1 (ii) the number of carbon-14...

The problem is: A 230-m-wide river has a uniform flow speed of 1.4 m/s through a jungle and toward the east. An explorer wishes to leave a small clearing on the south bank and cross the river in a powerboat that moves at a constant speed of 4.6 m/s with respect to the water. There is a clearing...

Homework Statement A boat moves across the water at a constant 30 mph towards the west. If the motor is generating a thrust of 500 M then the force of friction on the boat must be... a. 500 N to the east b. 500 N to the west c. less than 500 N to the east d. less than 500 N to the west...

Homework Statement How should you travel across a flowing river in a boat to minimize your time of travel? A) Straight across B) Slightly upstream C) Slightly downstream D) The time will be independent of how you head Homework EquationsThe Attempt at a Solution I thought the time would always...

Homework Statement A small boat weighing 1000 N has a surface area of 3 m^2. It floats only 5 cm above the water level when in a fresh-water lake. How high out of the water will it ride in a salt-water lake? Assume the surface area of the boat does not change as it rises (salt water has a...

Hi, I was trying to solve the following problem which was assigned to me in my Kinematics course. I found this solution for it. I understand the concept of relative velocity of the boat to the flowing river but what I really cannot understand is the trig part, of Vb/r : Vb/r = 5cos(theta)i -...

So I go into a debate this morning with a co-worker about a boat hull design. He is stating that if we create tunnels in the bottom of the boat that run longitudinally and are capped on the bottom but open on the ends they will trap water and act like ballast tanks thus adding stability when...

So her is my predicament. I plan to convert my car to a amphibious car. Don't be negative and judgemental about it but I need help to figure out how I should power it on water. I have a 1400 lbs car. It has a 67hp engine. What I'm thinking I want to do is have a sprocket/gear attached to my...

Homework Statement A boat pulls two barges down the river. The barge connected to the boat (barge A) has an inertia of 2x10^5 kg, and the other barge (barge B) has an inertia of 3x10^5 kg. the resistive force between barge A and the water is 7x10^3 N, and the resistive fore of barge B to the...

Original question: Two people (each of mass m) are standing on the stern of a boat of mass M. Ignoring friction, find the boat’s velocity v after they jump out with a horizontal velocity u relative to the boat’s initial velocity (a) if they jump together (b) if they jump one after another (c)...

I have built a model boat, ( http://schoolroad.weebly.com/rpgmodel_11.html ) and am trying to find out the amount of Power - maybe in Watts, that it takes to propel it at different speeds while it is running on the water. I have a rough sketch of the mechanism principle attached. When the...

A motor boat of mass m moves on the surface of a lake at a speed0v. At the moment 0t= the engine is shut down. Assuming the resistance of water to be proportional to the speed of the boat, F=−rv, find a) the time interval after which the boat stops; b) the speed of the boat as a function of...

hi all, here's the problem "A dog sits on the left end of a boat of length L that is initially adjacent to a dock to its right. The dog then runs toward the dock, but stops at the end of the boat. If the boat is H times heavier than the dog, how close does the dog get to the dock? Ignore...

I want to connect a lead-acid starting battery to a bank of deep discharge batteries on my boat via a diode. The purpose will be to let the start battery charge from the same source, but to not back feed. First, I'm unsure how to rate the diode. 12v is maximum voltage, that's clear. But...

A_________________________ - - W=45m - <------- Flow of the water - -...

Homework Statement A boat part from the point P of the bank of a river, with width D, and that flows with a constant velocity VR, and moves with a constant velocity VB, directed towars a point Q, located on the other side of the river directly in front of P. If r is the instantaneous distance...

Hello, I have recently been given an experiment, where i will need to build a boat. The requirements are ° the boat must have dimensions smaller than 8in x 8 in ° have a mass minimum of 25.0 grams °the weights when loaded into...

Homework Statement A 40 kg child stands at one end of a 70 kg boat that is 4 meters in length. The boat is initially 3 meters from the pier. The child notices a turtle on a rock near the far end of the boat and proceeds to walk to that end to catch the turtle. Neglect friction b/w the boat and...

Homework Statement 16. ) A row boat, starting from rest takes 11 seconds to travel 34 meters. If the boat maintains a uniform acceleration, what will be its instantaneous velocity at the end of the 11-second period?? 17.) At the point in the stream where the boat is crossing, the stream is 202...

The problem statement: You and a friend are in a boat in a river, the combined mass of this system is 200kg. The boat hits a rock and a hole of 1-cm diameter forms in the bottom of the boat, which is 20cm below the water line. 1) What is the gauge pressure of the water at the depth of the...

[b]1. A boat has a speed of 1.50 ms-1 in still water. It is used to cross a river 500 m wide along which there is a strong current of speed 0.900 ms-1. The boat is directed straight towards the opposite bank but the water current carries it downstream. Calculate: (A) the boat's speed relative...

a boat takes 3.1 hours to travel 15 km down a river, then takes 5.1 hours to travel the same distance upstream. how fast is the river traveling. I found the boat is traveling at 4.84km/hr down the stream and 2.94 km/hr up it. not sure where to go next. Any help would be appreciated.

Jerome and Paul are competitive brothers. They live on a small farm on the northern bank of a river that runs purely east and west and that flows to the east at a rate of 1.25 m/s. The brothers have run some time trials on the farm pond, and they know that, in still water, Jerome can paddle the...

i'm building my own floating dock. how do I calculate the volume of air I need to float a 1000 lbs boat completely out of the water? thank you

Homework Statement Dear all, I need help with an old exam question. It goes as following: The maximum power that a certain athlete can produce is equal to 1 kW. What is the theoretical maximum speed that a rower can obtain in a rowboat with a smooth exterior, a length of 4 meter and a 'wet'...

edit: woops I messed up the title. It should have been relative to the shore. Homework Statement A boat’s speed in still water is 1.95 . The boat is to travel directly across a river whose current has speed 1.10 . Determine the speed of the boat with respect to the shoreHomework Equations I'm...

I am building a jet boat as a project this year. I am going construct the impeller my self but don't know what dimensions I need to make it to get the most out of the engines without over loading them. Here's what I have to work with: The power source is going to be approximately 90 hp at...

Homework Statement A rectangular, flat-bottomed rowboat has a mass of 120 kg when empty. It's 3 meters long, 1 meter wide, and .24 meters deep. How many 85 kg people could it hold before swamping? Homework Equations d=m/v ? The Attempt at a Solution I need to determine the...

Homework Statement How many ways can a boat crew of 8 women be arranged if 3 of the women can only row on the bow side and 2 can only row on the stroke side?Homework Equations The Attempt at a Solution I simply did 8!/5! (5!/3!)3! which is simply 3!(8!/3!) The correct answer is 1728.

Homework Statement A boat crosses river, 240 m wide,which flows parallel to the straight banks with velocity v1 = 12i, while the velocity of the boat relative to the river is v2 = 5j where v1 and v2 are measure in m/s (i) find the magnitude of the actual velocity of the boat. (ii) find...

Hi forumers, I've got a question,and of course all proper answers are welcome, I think however a sailboat designer/engineer would quickly know what I'm talking about. I'd like to know what is the pressure/push of a 10 mph (16 km/h) wind on 12,000 sq.mt. surface ,and how to figure this...

This is a propeller on a boat, that is half in, half out, of the water. They provide more speed on light, fast boats. If you require more information, google "surface drive" or "wave piercing propeller". Companies like Arneson and Seafury manufacture these. Wikipeda has only 3-4 lines on it...

Homework Statement The deck of the boat is parallel to the dock as you jump from the boat and the direction of your velocity as you jump is 30° above the horizontal. If the boat was stationary when you jumped and 1.5 m away from the dock, what is the horizontal speed of the boat (in m/s) after...

When I went today after the bridge over the river, I thought... It's about how I see the situation. I noticed that just below me (under the bridge) was situated bow boat, sailing directly under the bridge. For how long, the boat will be on second side? How will the solution be different if I go...

Ok I had these 3 questions: I believe I have ansered the first 2 but I' am just stuck on the third. 1. an aircraft has a glide ratio of 12 to1 m, a building that is 45m high lies directly in the glide path, the plane clears the building by 12m, how far is the run way from the building? ANS: I...

Homework Statement A boat has a sail that has a surface S towards the wind. The wind blows at constant velocity u. Also given the density of the air, p. Find the velocity of the boat as a function of time. What will be the velocity of the boat after a long enough time? What exactly is this...

I'm clueless how to start!. Here is the description: A canal operating company is proposing to build an inclined plane to lift boats between two points with a vertical height difference of 55m. Currently the boats have to travel a distance of 6km through 19 canal locks to achieve the same...

Homework Statement Mary needs to row her boat across a 100-m-wide river that is flowing to the east at a speed of 1.0 m/s. Mary can row with a speed of 2.0 m/s. a) If Mary points her boat due north, how far from her intended landing spot will she be when she reaches the opposite shore? b)...

I am doing a rubber band powered boat for a project, but I'm not too sure as to what physics theory I can incorporate into it. We made a small wood board boat and powered in using rubber bands and tested to see how long it took to reach the end of the bath tub. Every time we added one more...

Homework Statement A man on a boat throws behind him a rock of mass m1=2kg with a velocity of v1=18m/s. The mass of a man with a boat is m_2=90kg. What velocty v_2 will the boat go with? Homework Equations v2 = (m1*v1)/m2 The Attempt at a Solution So I was upsent on the lesson...

I need "book smart" help with this boat design. Here is a picture of the design which I will explain in a minute...

A 200 kg canoe lies at rest in the water, near a dock but untethered. Any friction between the canoe and the water is negligible. A 60 kg man runs along the dock toward the boat and jumps in, at velocity v = 5 m/s (directed toward the long dimension of the canoe). The coefficient of friction...

Homework Statement A boat is capable of a constant speed of 4 m/s in a river that is flowing at 2 m/s. If the captain wishes to land 10m downriver while crossing a 50m river, then at what angle should the boat be aimed? Homework Equations...

Homework Statement A boat moves 15 km as it accelerates at 3.5 m/s^2 for 1.5 minutes. What is the truck's initial velocity? Homework Equations i'm stuck on what formula to use... [b]3. The Attempt at a Solution [/] vf^2=vo^2+2ax? ...

Homework Statement A speedy destroyer’s 5 inch gun fires a projectile at some angle to the horizontal. If the thing travels a distance of 23 500 m in 135 s, what was the projectile’s initial velocity? Homework Equations v=vi+at v^2=vi^2+2a(s) s=displacement s=vi*t+.5at^2 The...

Homework Statement The problem and its solution are attached as TheProblemAndSolution.jpg. Homework Equations Vector addition. Cross product. The Attempt at a Solution Given that I am just supposed to take Fig. 1 for what it is based on the way the problem is phrased, my biggest...