A 12000 kg boat is moving 4.25 m/s. Its engine pushes 9200 N forward, but the current pushes back at 12,500 N. How much times does it take the boat to stop?
A 12000 kg boat is moving 4.25 m/s. Its engine pushes 9200 N forward, but the...
An out-of-control 320 kg boat speeds at 15 m/s towards shore where several small children are playing. Wonder Woman steps in to stop the boat. If on average she can apply 1500 N of force, how long does it take her to stop the boat?
v = 2 m/s F = 100 N 3. (4 points) A child pushes a 20 kg box across a wood floor as shown in Figure 3. The force exerted by the child is 100 N and horizontal. If the box is moving with a constant speed, 2 m/s. (a). Find the magnitude and the direction of the kinetic friction force on the box (b). Determine the coefficient of kinetic friction between the box and the floor. (C). If the...
A 12 kg block is pressed against a spring with spring constant k = 1424 N/m. The spring is normally 65 cm long but the block is pressed against it to compress the spring until it is only 27 cm long. The block is then released and the spring pushes it forward onto a frictionless surface. a)How fast is the block moving immediately after it leaves the spring? b) The mass then slides across a 2.5 m wide surface with...
Jack and Jill are in a boat 4 m long. The boat has mass 48 kg and its weight is uniformly distributed along its length. Jill (mass 30 kg) sits at one end and Jack (mass 45 kg) sits at the other end. The boat is in still water, not moving as children stay still. If Jack and Jill exchange their positions, by how much does the boat move? Ignore any resistance of the lake's water.
the blade of a lawn mower is a 4.25 kg. 74.5 cm long metal (with a shape similar to a meter stick) with a hole at its midpoint. The blade is attached to the engine axle by a bolt through the center hole. when started, the blade accelerates to the full speed at 375 rpm in 5.25 seconds. a) what is the angular acceleration of the blade? b) how fast is blade edge moving 2.55 s after it start? c)...
An alpha particle (m = 4.002602 u) is moving at 3.60 times 10^2 m/s. a) Find its mass in kilograms. (6.64 times 10^-27 kg) b) Find its kinetic energy. (4.30 times 10^-22 J) c) Find its kinetic energy in MeV. (2.69 times 10^-9 MeV) d) Find its momentum. (2.39 times 10^-24 kg. m/s) e) Find its deBroglie wavelength (2.77 times 10^-10 m = 0.277 nm) A stationary nucleus of protactinium-231 (m = 231.035879 u) decays by alpha radiation to a...
A boat with mass of 1 200 kg is traveling at 12 m/s. What is the magnitude of the force required to stop the boat if it undergoes a displacement of 85 m? a. 1 000 N b. 8 500 N c. 2 000 N d. 170 N
A river is moving east at vWE = 3.97 m/s. A boat starts from the dock heading θ = 33.9 degrees north of west at vBW = 9.12 m/s, relative to the water. The river is w = 1380 m wide. Part (a) Write an expression for the speed of the boat with respect to Earth (vBE) in terms of variables from the problem statement. B) Write an expression for the time t it takes the boat to cross the...
A boat can travel at a speed of 4 m/s in still water. A river that is 170 m wide has a current that flows 0.85 m/s due West. a) If the boat points its bow directly across the river, how fast does the boat travel relative to the shore? m/s b) How long will it take to cross the river? s c) How far downriver will it land (the distance on the bank from the point directly across from...
A man pushes a lawn mower on a level lawn with a force of 207 N. If 35% of this force is directed forward, how much power does he expend in pushing the mower 6.6 m in 10 s?