Q2. Figure 7-14 shows constant forces F1 and F2 acting on a box as the box slides rightward across a frictionless floor. Force F1 is horizontal, with magnitude 2.0 N; force F2 is angled upward by 60° to the floor and has magnitude 4.0 N. The speed v of the box at a certain instant is 3.0 m/s. What is the power due to each force acting on the box at that instant, and what is the net power? Is the net power changing at that instant? Negative power. (This force is Positive power. T (This force is removing energy.) supplying energy.) 60 Frictionless Eaut Fig. 7-14 Two forces F, and F, act on a box that slides rightward across a frictionless floor. The velocity of the box is v.

Q2. Figure 7-14 shows constant forces F1 and F2 acting on a box as the box slides rightward across a frictionless floor. Force F1 is horizontal, with magnitude 2.0 N; force F2 is angled upward by 60° to the floor and has magnitude 4.0 N. The speed v of the box at a certain instant is 3.0 m/s. What is the power due to each force acting on the box at that instant, and what is the net power? Is the net power changing at that instant? Negative power. (This force is Positive power. T (This force is removing energy.) supplying energy.) 60 Frictionless Eaut Fig. 7-14 Two forces F, and F, act on a box that slides rightward across a frictionless floor. The velocity of the box is v.

Classical Dynamics of Particles and Systems

5th Edition

ISBN:9780534408961

Author:Stephen T. Thornton, Jerry B. Marion

Publisher:Stephen T. Thornton, Jerry B. Marion

Chapter2: Newtonian Mechanics-single Particle

Section: Chapter Questions

Problem 2.13P: A particle moves in a medium under the influence of a retarding force equal to mk(υ3+ a2υ), where k...

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A particle moves in a medium under the influence of a retarding force equal to mk(υ3+ a2υ), where k and a are constants. Show that for any value of the initial speed the particle will never move a distance greater than π/2kaand that the particle comes to rest only for t → ∞.
An athlete jumping vertically on a trampoline leaves the surface with a velocity of 8.5 m/s upward. What maximum height does she reach? (a) 13 m (b) 2.3 m (c) 3.7 m (d) 0.27 m (e) The answer cant be determined because the mass of the athlete isnt given.
Problems 67. 70. 71. and 72 are grouped. A A block of mass M is placed on a frictionless plane. The plane is inclined at an angle , and the block is a distance d from its end. Of course, we would expect the block to slip down the plane. Suppose we revolve the incline around the vertical axis shown in Figure P6.67 instead. At what period of revolution will the block remain in place on the plane? FIGURE P6.67 Problems 67. 71. and 72.
A cart is set rolling across a level table, at the same speed on every trial. If it runs into a patch of sand, the cart exerts on the sand an average horizontal force of 6 N and travels a distance of 6 cm through the sand as it comes to a stop. It instead the cart runs into a patch of gravel on which the can exerts an average horizontal force of 9 N, how far into the gravel will the cart roll before stopping? (a) 9 cm (b) 6 cm (c) 4 cm (d) 3 cm (e) none of those answers
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