Ug m2 Figure P9.18

The fisherman's mass is 70 kg, and the rowboat's is 119 kg. The fisherman and rowboat are initially at rest when the fisherman throws a package of mass m = 15 kg horizontally to the right with a speed of vi = 4.7 m/s. What is the velocity of the rowboat after the package is thrown? Neglect any resistance force from the water. (Give the magnitude in m/s, and select the correct direction from the options given.) A fisherman in a rowboat throws a package of mass m to the right with velocity vector vi. magnitude                       m/s toward what direction

An outlaw cuts loose a wagon with two boxes of gold, of total mass 300 kg, when the wagon is at rest 50 m up a 6.0° slope. The outlaw plans to have the wagon roll down the slope and across the level ground, and then fall into a canyon where his accomplices wait. But in a tree 40 m from the canyon’s cliff wait the Lone Ranger (mass 75.0 kg) and Tonto (mass 60.0 kg). They drop vertically into the wagon as it passes beneath them (Fig.). (a) If they require 5.0 s to grab the gold and jump out, will they make it before the wagon goes over the cliff? The wagon rolls with negligible friction. (b) When the two heroes drop into the wagon, is the kinetic energy of the system of heroes plus wagon conserved? If not, does it increase or decrease, and by how much?

The mass of a particular skateboard plus its rider is m, = 76.6 kg, and the skateboarder is holding a book with mass mo = 3.27 kg. Initially atrest, the skateboarder tosses the textbook with a velocity of vb = 4.44 m/s at an angle 0 = 23.3° above the horizontal, and the book is caught by a friend.

A freight train is being assembled in a switching yard, with two boxcars. Car 1 has a mass of m1= 61x10^3 kg and moves at a velocity of Vo1= +1 m/s. Car 2, with a mass of m2= 92x10^3 kg and a velocity 0f Vo2= +1 m/s, overtakes car ! and couples to it. Neglecting friction, find the common velocity (m/s) of the cars after they become coupled. Express in 3 decimal places.

A space probe, initially at rest, undergoes an internal mechanical malfunction and breaks into three pieces. One piece of mass m1 = 48.0 kg travels in the positive x -direction at 12.0 m/s, and a second piece of mass m2 = 62.0 kg travels in the xy -plane at an angle of 105° at 15.0 m/s. The third piece has mass m3 = 112 kg. (a) Sketch a diagram of the situation, labeling the different masses and their velocities. (b) Write the general expression for conservation of momentum in the x and y -directions in terms of m1, m2, m3, v1, v2 and v3 and the sines and cosines of the angles, taking u to be the unknown angle. (c) Calculate the final x -components of the momenta of m1 and m2 . (d) Calculate the final y -components of the momenta of m1 and m2 . (e) Substitute the known momentum components into the general equations of momentum for the xand y -directions, along with the known mass m3, v3 cos0  and v3 sin0 , respectively, and use the identity cos0 + sin20 = 1 to obtain v3 . (g) Divide…

A small block of mass m, - 0.755 kg is released from rest at the top of a curved wedge of mass m, = 3.50 kg, which sits on a frictionless horizontal surface as in figure (a). When the block leaves the wedge, its velocity is measured to be 4.00 m/s to the right, as in figure (b). m2 4.00 m/s (a) What is the velocity of the wedge after the block reaches the horizontal surface? (Enter the magnitude of the velocity.) m/s (b) What is the height h of the wedge?

A baseball (m = 148 g) approaches a bat horizontally at a speed of 40.7 m/s (91.1 mi/h) and is hit straight back at a speed of 51.6 m/s (115 mi/h). If the ball is in contact with the bat for a time of 1.45 ms, what is the average force exerted on the ball by the bat? Neglect the weight of the bat, since it is so much less than the force of the bat. Choose the direction of the incoming ball as the positive direction.