10:02Newton's 2nd Law (2 of 21) Calculate Acceleration with Friction, Net Force HorizontalStep by Step Science548views
Multiple ChoicePushing a 10-kg toolbox across the floor, you find that the box moves at a constant speed when you push horizontally with a force of 39 N. What is the coefficient of kinetic friction between the floor and the toolbox?1272views21rank1comments
Multiple ChoiceYou push on a 3-kg box to give it an initial speed of 5 m/s across a floor. If μk = 0.3, how far does the box travel before coming to a stop?1076views25rank2comments
Multiple ChoiceBlock A, mass 250g, sits on top of block B, mass 2.0kg. The coefficients of static and kinetic friction between blocks A and B are 0.34 and 0.23, respectively. Block B sits on a frictionless surface. What is the maximum horizontal force that can be applied to block B, without block A slipping?405views
Textbook QuestionIn a laboratory experiment on friction, a 135-N block resting on a rough horizontal table is pulled by a horizontal wire. The pull gradually increases until the block begins to move and continues to increase thereafter. Figure E5.26 shows a graph of the friction force on this block as a function of the pull. (a) Identify the regions of the graph where static friction and kinetic friction occur. 1110views
Textbook QuestionA box of bananas weighing 40.0 N rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.40, and the coefficient of kinetic friction is 0.20. (e) If the monkey applies a horizontal force of 18.0 N, what is the magnitude of the friction force and what is the box's acceleration?414views
Textbook QuestionA box of bananas weighing 40.0 N rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.40, and the coefficient of kinetic friction is 0.20. (d) What minimum horizontal force must the monkey apply to keep the box moving at constant velocity once it has been started?394views
Textbook QuestionA 45.0-kg crate of tools rests on a horizontal floor. You exert a gradually increasing horizontal push on it, and the crate just begins to move when your force exceeds 313 N. Then you must reduce your push to 208 N to keep it moving at a steady 25.0 cm/s. (b) What push must you exert to give it an acceleration of 1.10 m/s2?891views2rank
Textbook QuestionA 45.0-kg crate of tools rests on a horizontal floor. You exert a gradually increasing horizontal push on it, and the crate just begins to move when your force exceeds 313 N. Then you must reduce your push to 208 N to keep it moving at a steady 25.0 cm/s. (a) What are the coefficients of static and kinetic friction between the crate and the floor?2019views
Textbook QuestionYou throw a baseball straight upward. The drag force is proportional to υ2. In terms of g, what is the y-component of the ball's acceleration when the ball's speed is half its terminal speed and (b) It is moving back down?1502views
Textbook QuestionYou throw a baseball straight upward. The drag force is proportional to υ2. In terms of g, what is the y-component of the ball's acceleration when the ball's speed is half its terminal speed and (a) it is moving up?553views
Textbook Question(b) If the skydiver's daughter, whose mass is 45 kg, is falling through the air and has the same D (0.25 kg/m) as her father, what is the daughter's terminal speed?385views
Textbook QuestionA 45.0-kg crate of tools rests on a horizontal floor. You exert a gradually increasing horizontal push on it, and the crate just begins to move when your force exceeds 313 N. Then you must reduce your push to 208 N to keep it moving at a steady 25.0 cm/s. (c) Suppose you were performing the same experiment on the moon, where the acceleration due to gravity is 1.62 m/s2. (i) What magnitude push would cause it to move? (ii) What would its acceleration be if you maintained the push in part (b)?268views
Textbook Question(II) Police investigators, examining the scene of an accident involving a car and an old truck, measure 72-m-long skid marks for the truck, which nearly came to a stop before colliding with the car at rest. The coefficient of kinetic friction between rubber and the pavement is about 0.80. Estimate the initial speed of the truck assuming a level road.147views
Textbook QuestionSo-called volcanic 'ash' is actually finely pulverized rock blown high into the atmosphere. A typical ash particle is a 50-micrometer-diameter piece of silica with a density of 2400 kg/m^3. (b) How long in hours does it take this ash particle to fall from a height of 5.0 km in still air? Use the properties of 20°C air at sea level.1076views1comments
Textbook QuestionWhat is the magnitude of the acceleration of a skydiver at the instant she is falling at one-half her terminal speed?670views
Textbook QuestionAn E. coli bacterium can be modeled as a sphere that has the density of water. Rotating flagella propel a bacterium through 40°C water with a force of 65 fN, where 1 fN = 1femtonewton = 10^-15 N. What is the bacterium's speed in micrometers/s?381views
Textbook QuestionAn object with cross section A is shot horizontally across frictionless ice. Its initial velocity is v₀ₓ at t₀ = 0 s. Air resistance is not negligible. a. Show that the velocity at time t is given by the expression vₓ = v₀ₓ --------------- 1 + C𝓭pAv₀ₓt / 2m314views
Textbook QuestionA 1.0-cm-diameter, 2.0 g marble is shot horizontally into a tank of 20°C olive oil at 10 cm/s. How far in cm will it travel before stopping?282views
Textbook Questionb. A 4.0-cm-diameter, 55 g ball is shot horizontally into a tank of 40°C honey. How long will it take for the horizontal speed to decrease to 10% of its initial value?348views
Textbook Questiona. A spherical particle of mass m is shot horizontally with initial speed v₀ into a viscous fluid. Use Stokes' law to find an expression for vₓ (t), the horizontal velocity as a function of time. Vertical motion due to gravity can be ignored.417views
Textbook QuestionA medium-sized jet has a 3.8-m-diameter fuselage and a loaded mass of 85,000 kg. The drag on an airplane is primarily due to the cylindrical fuselage, and aerodynamic shaping gives it a drag coefficient of 0.37. How much thrust must the jet's engines provide to cruise at 230 m/s at an altitude where the air density is 1.0 kg/m^31543views
Textbook QuestionSo-called volcanic 'ash' is actually finely pulverized rock blown high into the atmosphere. A typical ash particle is a 50-micrometer-diameter piece of silica with a density of 2400 kg/m^3. (a) How long would it take this ash particle to fall from a height of 5.0 km in vacuum?397views
Textbook Question(b) Below what speed does a 3.0-mm-diameter ball bearing in 20°C air experience linear drag?321views
Textbook Question(a) Above what speed does a 3.0-mm-diameter ball bearing in 20°C water experience quadratic drag?547views
Textbook QuestionA ball is shot from a compressed-air gun at twice its terminal speed. a. What is the ball's initial acceleration, as a multiple of g, if it is shot straight up?811views
Textbook QuestionA 10 kg crate is placed on a horizontal conveyor belt. The materials are such that mu(s) = 0.5 and mu(k) = 0.3. (b) Draw a free-body diagram showing all the forces on the crate if the conveyer belt is speeding up.779views
Textbook QuestionA 250 g ball is launched with a speed of 35 m/s at a 30° angle. A strong headwind exerts a constant horizontal drag force on the ball. What is the magnitude of the drag force if the wind reduces the ball's travel distance by 20%?759views
Textbook QuestionA 68-kg water skier is being accelerated by a ski boat on a flat ('glassy') lake. The coefficient of kinetic friction between the skier's skis and the water surface is μₖ = 0.25 (Fig. 5–59).<IMAGE>(a) What is the skier's acceleration if the rope pulling the skier behind the boat applies a horizontal tension force of magnitude F_T = 240N to the skier (θ = 0°)?114views
Textbook QuestionA 68-kg water skier is being accelerated by a ski boat on a flat ('glassy') lake. The coefficient of kinetic friction between the skier's skis and the water surface is μₖ = 0.25 (Fig. 5–59).<IMAGE>(b) What is the skier's horizontal acceleration if the rope pulling the skier exerts a force of F_T = 240N on the skier at an upward angle θ = 12° ?178views
Textbook Question(II) A package of mass m is dropped vertically onto a horizontal conveyor belt whose speed is v=1.5m/s , and the coefficient of kinetic friction between the package and the belt is μₖ = 0.70.(a) For how much time does the package slide on the belt (until it is at rest relative to the belt)?262views
Textbook Question(II) A package of mass m is dropped vertically onto a horizontal conveyor belt whose speed is v=1.5m/s , and the coefficient of kinetic friction between the package and the belt is μₖ = 0.70.(b) How far does the package move during this time?180views
Textbook QuestionA 68-kg water skier is being accelerated by a ski boat on a flat ('glassy') lake. The coefficient of kinetic friction between the skier's skis and the water surface is μₖ = 0.25 (Fig. 5–59).<IMAGE>(c) Explain why the skier's acceleration in part (b) is greater than that in part (a).194views
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