A 3.26 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.4 N at an angle theta = 29.0° above the horizontal. The coefficient of kinetic friction between the block and
62,309 results

physics
A 3.26 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.4 N at an angle theta = 29.0° above the horizontal. The coefficient of kinetic friction between the block and the floor is 0.10. What is the speed of the block 3.1 s after it starts ... 
physics
A 3.26 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.4 N at an angle theta = 29.0° above the horizontal. The coefficient of kinetic friction between the block and the floor is 0.10. What is the speed of the block 3.1 s after it starts ... 
physics
A 5.56 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.7 N at an angle theta = 17.0° above the horizontal, as shown in the Figure. The coefficient of kinetic friction between the block and the floor is 0.06. What is the speed of the block... 
Physics
A 4.58 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.5 N at an angle theta = 25.5° above the horizontal. The coefficient of kinetic friction between the block and the floor is 0.09. What distance does the block travel in a time of 5.90 ... 
Physics
A 4.96 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=13.7N at an angle theta=16.0degrees above the horizontal. What is the magnitude of the acceleration of the block when the force is applied? I know a=F/m 
physics
A 3.24 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=11.8N at an angle theta=23.0degrees above the horizontal, as shown. What is the magnitude of the acceleration of the block when the force is applied? 
physics
A 4.5 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=13.50 N at an angle theta=30.0 degrees above the horizontal. What is the speed of the block 5.50 seconds after it starts moving? 
physics
A 3.24 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=11.8N at an angle theta=23.0degrees above the horizontal, as shown. What is the magnitude of the acceleration of the block when the force is applied? b.) What is the horizontal... 
Physics
A 5.70 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.4 N at an angle theta = 27.5° above the horizontal. The coefficient of kinetic friction between the block and the floor is 0.10. What is the speed of the block 6.1 s after it starts ... 
physics
I am trying to study for my exam i have tomorrow and this type of problem keeps giving me trouble can someone please help me:: A 3.24 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=11.8N at an angle theta=23.0degrees above the ... 
physics
A 6.00 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=14.1 N at an angle θ= 19.0° above the horizontal, as shown. What is the speed of the block 3.50 seconds after it starts moving? 
physics
A 6.00 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=14.1 N at an angle θ= 19.0° above the horizontal, as shown. What is the speed of the block 3.50 seconds after it starts moving? 
physics
A 3.90 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=14.1N at an angle theta=32.5degrees above the horizontal, as shown. a.) What is the magnitude of the acceleration of the block when the force is applied? b.) What is the ... 
Physics
A block of mass 7.5 kg is pulled along a horizontal frictionless floor by a cord that exerts a force of 31.0 N at an angle 26.3° above the horizontal. What is the magnitude of the acceleration of the block? I have nooo clue what to do for this one. Can someone please show me ... 
Physics
Problem:: A 4.80 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=13.5 N at an angle q= 17.5° above the horizontal. What is the speed of the block 3.90 seconds after it starts moving? What I've got:: Using sin and cos, I've got ... 
Physics
A 5.1–kg block is pulled along a frictionless floor by a cord that exerts a force P = 12 N at an angle θ = 25° above the horizontal, as shown below. (a) What is the acceleration of the block? (b) The force P is slowly increased. What is the value of P just before the ... 
Physics
A block of mass 8.60 kg is pulled along a horizontal frictionless surface by a cord that exerts a force of 33 N at an angle 29.40 degrees from the horizontal. What is the magnitude of the normal force exerted on the mass by the floor? I solved for the acceleration, which was 3... 
Phy
In the figure, a block of mass m = 3.09 kg is pulled along a horizontal frictionless floor by a cord that exerts a force of magnitude F = 13.7 N at an angle θ = 23.0°. (a) What is the magnitude of the block's acceleration? (b) The force magnitude F is slowly increased. ... 
Physics/Math
A 3.0 kg block, initially in motion, is pushed along a horizontal floor by a force F of magnitude 18 N at an angle = 45° with the horizontal. The coefficient of kinetic friction between the block and floor is 0.25. (Assume the positive direction is to the right.) Calculate ... 
physics
A block rests on a horizontal frictionless surface. A string is attached to the block, and is pulled with a force of 60.0 N at an angle θ above the horizontal. After the block is pulled through a distance of 2.00 m, its speed is 2.70 m/s, and 43.0 J of work has been done ... 
Physics
A)A block rests on a horizontal frictionless surface. A string is attached to the block, and is pulled with a force of 60.0 N at an angle θ above the horizontal. After the block is pulled through a distance of 2.00 m, its speed is 2.70 m/s, and 43.0 J of work has been ... 
Physics
A block rests on a horizontal, frictionless surface. A string is attached to the block, and is pulled with a force of 45.0 N at an angle è above the horizontal, as shown in Figure 723. After the block is pulled through a distance of 1.50 m its speed is v = 2.90 m/s, and 50.0... 
Physics
A block rests on a horizontal, frictionless surface. A string is attached to the block, and is pulled with a force of 45.0 N at an angle è above the horizontal, as shown in Figure 723. After the block is pulled through a distance of 1.50 m its speed is v = 2.90 m/s, and 50.0... 
PHYSICS
A 6.53kg block initially at rest is pulled to the right along a horizontal surface by a constant force of 125 N applied at an angle θ above the horizontal. The coefficient of kinetic friction between the block and the horizontal surface is 0.150. At what angle θ above the ... 
physics
A 5 kg block is pulled along a horizontal frictionless floor by a string and exerts force of magnitude 16 N at an angle 30 degree.What is the magnitude of the acc of block? 
Physics
A 70 kg block is pulled at a constant speed of 6.4 m/s across a horizontal floor by an applied force of 102 N directed 37° above the horizontal. What is the rate at which the force does work on the block? 
Physics
A 70 kg block is pulled at a constant speed of 6.4 m/s across a horizontal floor by an applied force of 102 N directed 37° above the horizontal. What is the rate at which the force does work on the block? 
Physics
A 70 kg block is pulled at a constant speed of 6.4 m/s across a horizontal floor by an applied force of 102 N directed 37° above the horizontal. What is the rate at which the force does work on the block? 
physics
A 180 kg block is pulled at a constant speed of 8.3 m/s across a horizontal floor by an applied force of 135 N directed 15° above the horizontal. What is the rate at which the force does work on the block? 
PHYSICS
A 3.5 kg block is pushed along a horizontal floor by a force of magnitude 15 N at an angle 40° with the horizontal (Fig. 619). The coefficient of kinetic friction between the block and the floor is 0.25. Calculate the magnitudes of (i) the frictional force on the block from ... 
Physic
A 3.5 kg block is pushed along a horizontal floor by a force of magnitude 15 N at an angle è = 40° with the horizontal. The coefficient of kinetic friction between the block and the floor is 0.25. Calculate the magnitudes of (a) the frictional force on the block from the ... 
physics
A block is pulled across the floor by a pull of 400 N at an angle of 35˚ with the horizontal. The force of the kinetic friction is 150 N, and the block is moved a horizontal distance of 23 m. What is the resultant work? 
Physics
A wooden block of mass 9 kg is at rest on an inclined plane sloped at an angle theta from the horizontal. The block is located 5 m from the bottom of the plane. A) Find the frictional force for theta = 20 B)If the angle is increased slowly the block starts sliding at an angle ... 
physics
A 10KG block is pulled along a rough horizontal floor by a 12N force acting at a 30 degrees angle with respect to the horizontal. The block accelerates at 0.1 m/s2. Calculate A....... the weight of the block B...... the force of friction acting on the block C.... the normal ... 
physics
A 10KG block is pulled along a rough horizontal floor by a 12N force acting at a 30 degrees angle with respect to the horizontal. The block accelerates at 0.1 m/s2. Calculate A....... the weight of the block B...... the force of friction acting on the block C.... the normal ... 
Physics
A 10KG block is pulled along a rough horizontal floor by a 12N force acting at a 30 degrees angle with respect to the horizontal. The block accelerates at 0.1 m/s2. Calculate A....... the weight of the block B...... the force of friction acting on the block C.... the normal ... 
Re: Physics/Math
A 3.0 kg block, initially in motion, is pushed along a horizontal floor by a force F of magnitude 18 N at an angle = 45° with the horizontal. The coefficient of kinetic friction between the block and floor is 0.25. (Assume the positive direction is to the right.) Calculate ... 
physics
A rope is used to pull a 2.54 kg block at constant speed 4.48 m along a horizontal floor. The force on the block from the rope is 5.87 N and directed 29.8° above the horizontal. What are (a) the work done by the rope's force, (b) the increase in thermal energy of the block... 
Physics
A rope is used to pull a 5.19 kg block at constant speed 3.38 m along a horizontal floor. The force on the block from the rope is 3.23 N and directed 20.0° above the horizontal. What are (a) the work done by the rope's force, (b) the increase in thermal energy of the block... 
college physics
A rope is used to pull a 3.57 kg block at constant speed 5.10 m along a horizontal floor. The force on the block from the rope is 6.82 N and is directed 15° above the horizontal. (a)What is the work done by the rope's force? (b) What is the increase in the thermal energy of ... 
Physics
A stationary arrangement of two crayon boxes and three cords. Box A has a mass of 11.0kg and is on a ramp at angle è=30.0 degrees; box B has a mass of 7.00 kg and hangs on a cord. The cord connected to Box A is parallel to the ramp which is frictionless (a) What is the ... 
Physics
A block of mass 3.42 kg is drawn at constant speed a distance of 1.32 m along a horizontal floor by a rope exerting a constant force of magnitude 8.62 N and making an angle of 17.0 degrees above the horizontal. Compute the coefficient of friction between the block and the floor. 
Physics
A block of mass 3.42 kg is drawn at constant speed a distance of 1.32 m along a horizontal floor by a rope exerting a constant force of magnitude 8.62 N and making an angle of 17.0 degrees above the horizontal. Compute the coefficient of friction between the block and the floor. 
Physics
A small block with a mass of m = 0.120 kg is attached to a cord passing through a hole in a frictionless, horizontal surface. The block is originally revolving at a distance of 0.40 m from the hole with a speed of 0.70 m/s. The cord is pulled from below, shortening the radius ... 
Physics
I got two questions Three blocks on a fricitonless horizontal surface are in contact with each other a force F is applied to block 1 mass m1 Draw a free body diagram for each block ok done the accelration of the system (in terms of m1, m2, and m3) ok done I got a = (m1 + m2 + ... 
physics
A 3.0 kg block is pushed along a horizontal floor by a force F of magnitude 19 N at an angle θ = 30° with the horizontal. The coefficient of kinetic friction between the block and floor is 0.25.(a) Calculate the magnitude of the frictional force on the block from the ... 
college physics
find the frictional force exerted on a 20kg block pulled slowly over a horizontal floor using a rope which makes a 30 degree angle over the horizontal. the pulling force is 100N??? i found the Fn to be 146 N what do i do from there? 
mechanics
A block of wood is pulled along a Horizontal table by a force of 33 N inclined at 30 degrees above the Horizontal.Find the vertical and horizontal components of the force. 
Mechanics & hydromechanics
A block of wood is pulled along a Horizontal table by a force of 33 N inclined at 30 degrees above the Horizontal.Find the vertical and horizontal components of the force. 
phy
(Q1)A 40N force applied at an angle of 37c above the horizontal pulls a 5kg box on a horizontal floor. The acceleration of the box is 3m/s2,How large a frctional force must be retarding the motion of the box. (a)50 N(b)13N(c)17N(d)25N (Q2) A block of mass 2kg is connected to a... 
physics
A 3.5 kg block, initially in motion, is pushed along a horizontal floor by a force F of magnitude 17 N at an angle θ = 35° with the horizontal (Figure 620). The coefficient of kinetic friction between the block and floor is 0.25. (Assume the positive direction is to the... 
A 3.5 kg block, initially in motion, is pushed along a horizontal floor by a force F of magnitude 17 N at an angle θ = 35° with the horizontal (Figure 620). The coefficient of kinetic friction between the block and floor is 0.25. (Assume the positive direction is to the...

Physics
A 7 kg block is pulled 8 m along a frictionless horizontal plane by a 23 N force that acts at 39 degrees above the horizontal. What is the work done by the force on the block? I don't get how to start the problem, I feel like there is something missing. 
science
A chair of mass 15.5 is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force = 38.0 that is directed at an angle of 42.0 below the horizontal and the chair slides along the floor.Use Newton's laws to calculate the normal force that... 
physics
A chair of weight 150 lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of = 38.0 directed at an angle of 41.0 below the horizontal and the chair slides along the floor.Using Newton's laws, calculate , the magnitude of the normal ... 
physics
A chair of weight 150 lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of = 38.0 directed at an angle of 41.0 below the horizontal and the chair slides along the floor.Using Newton's laws, calculate , the magnitude of the normal ... 
physics
A chair of weight 150 lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of = 38.0 directed at an angle of 41.0 below the horizontal and the chair slides along the floor.Using Newton's laws, calculate , the magnitude of the normal ... 
physics
A chair of weight 150 lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of = 38.0 directed at an angle of 41.0 below the horizontal and the chair slides along the floor.Using Newton's laws, calculate , the magnitude of the normal ... 
Physics
A chair of weight 85.0 N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 44.0 N directed at an angle of 42.0 degrees below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the ... 
physics
A chair of weight 150 lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of = 36.0 directed at an angle of 40.0 below the horizontal and the chair slides along the floor.Using Newton's laws, calculate , the magnitude of the normal ... 
physics
A chair of weight 150 lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of = 36.0 directed at an angle of 40.0 below the horizontal and the chair slides along the floor.Using Newton's laws, calculate , the magnitude of the normal ... 
Physics
A chair of weight 85.0N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 45.0N directed at an angle of 34.0∘ below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the magnitude ... 
physics
A 3.5 kg block, initially in motion, is pushed along a horizontal floor by a force F of magnitude 19 N at an angle θ = 45° with the horizontal. The coefficient of kinetic friction between the block and floor is 0.25. (Assume the positive direction is to the right.) 
Physics
A chair of weight 75.0N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 45.0N directed at an angle of 40.0¡ã below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the magnitude of ... 
Re: Physics/Math
A sphere of mass 2.7 x 10^4 kg is suspended from a cord. A steady horizontal breeze pushes the sphere so that the cord makes a constant angle of 41 degrees with the vertical. Find the magnitude of the push provided by the breeze and Find the tension in the cord. you have a ... 
physics
A chair of weight 100N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 43.0N directed at an angle of 35.0^\circ below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the magnitude of ... 
physics
A chair of weight 100N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 43.0N directed at an angle of 35.0^\circ below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the magnitude of ... 
physics
On take off, the combined action of the engines and wings of an airplane exerts a(n) 7767 N force on the plane,directed upward at an angle of 59.1 degrees above the horizontal. The plane rises with constant velocity in the vertical direction while continuing to accelerate in ... 
physics
A mass m = 17 kg is pulled along a horizontal floor with NO friction for a distance d =5.4 m. Then the mass is pulled up an incline that makes an angle θ = 32° with the horizontal and has a coefficient of kinetic friction μk = 0.36. The entire time the massless rope used to... 
Physics 1
A horizontal force of 30 N pulls a block of mass 2.5 kg across a level floor. The coefficient of kinetic friction between the block and the floor is μK = 0.25. If the block begins with a speed of 2.0 m/s and is pulled for a distance of 18 m, what is the final speed of the... 
RepostPhysics 1
A horizontal force of 30 N pulls a block of mass 2.5 kg across a level floor. The coefficient of kinetic friction between the block and the floor is ìK = 0.25. If the block begins with a speed of 2.0 m/s and is pulled for a distance of 18 m, what is the final speed of the ... 
physics
A 3.0kg block is on a frictionless horizontal surface. The block is at rest when, at t = 0, a force (magnitude P = 2.0 N) acting at an angle of 22° above the horizontal is applied to the block. At what rate is the force P doing work at t = 2.0 s? A. 2.3 W B. 2.0 W C. 1.4 W D... 
physics
A mass m = 17.0 kg is pulled along a horizontal floor with NO friction for a distance d =5.1 m. Then the mass is pulled up an incline that makes an angle è = 30.0° with the horizontal and has a coefficient of kinetic friction ìk = 0.34. The entire time the massless rope ... 
Physics
A 4 kg block resting on a horizontal surface is attached to an 8 kg block that hangs freely by a cord passing over a frictionless pulley. The coefficient of kinetic friction between the block and the horizontal surface is 0.4. Find the acceleration of the blocks and the ... 
Physics
A horizontal force of 100 N pushes a 12kg block up a frictionless incline that makes an angle 25degrees with the horizontal. What is the normal force that the incline exerts on the block and what is the acceleration of the block? I found part (a) which is the normal force. It ... 
Physics
I'm tyring to undersatnd uh motion of a particle at an incline on a ramp with a certain angle with the horizontal. the force pointing downwards is mg the force that is pointing upwards exerted by the ramp onto the the particle is the normal force which is not pointing ... 
physics
A 1,040N crate is being pushed across a level floor at a constant speed by a force of 350 N at an angle of 20.0° below the horizontal; (a) What is the coefficient of kinetic friction between the crate and the floor? (b) If the 350N force is instead pulling the block at an ... 
physics
A 1100 N crate is being pushed across a level floor at a constant speed by a force of 500 N at an angle of 20.0° below the horizontal. (a) What is the coefficient of kinetic friction between the crate and the floor? (b) If the 500 N force is instead pulling the block at an ... 
physics
A 23.1 kg block is dragged over a rough, horizontal surface by a constant force of 95.0 N acting at an angle of angle 29.3 ° above the horizontal. The block is displaced 5.50 m, and the coefficient of kinetic friction is 0.341. Find the magnitude of the work done by the ... 
Physics
A 19.5 kg block is dragged over a rough, horizontal surface by a constant force of 110 N acting at an angle of angle 31.1◦ above the horizontal. The block is displaced 6.74 m,and the coefficient of kinetic friction is 0.156. What is the net work done on the block? Answer... 
Physics
A 19.5 kg block is dragged over a rough, horizontal surface by a constant force of 110 N acting at an angle of angle 31.1◦ above the horizontal. The block is displaced 6.74 m,and the coefficient of kinetic friction is 0.156.What is the net work done on the block? Answer ... 
PHYSICS: Conservative Forces and Potential Energy
A mass m = 18 kg is pulled along a horizontal floor with NO friction for a distance d =6.6 m. Then the mass is pulled up an incline that makes an angle θ = 38° with the horizontal and has a coefficient of kinetic friction μk = 0.44. The entire time the massless rope... 
physical aspects of nature
A 1,440N crate is being pushed across a level floor at a constant speed by a force of 250 N at an angle of 20.0° below the horizontal; (a) What is the coefficient of kinetic friction between the crate and the floor? (b) If the 250N force is instead pulling the block at an ... 
PHYSICS
QUIZ 1 AND 2, PROBLEM 3 A block of mass M is pulled with a rope that exerts a force of a magnitude F, causing it to slide over horizontal ground with kinetic coefficient of friction μ (use "mu" when you input your answer). The force is applied at angle θ (use "theta... 
physics
A mass m = 17 kg is pulled along a horizontal floor with NO friction for a distance d =5.4 m. Then the mass is pulled up an incline that makes an angle θ = 32° with the horizontal and has a coefficient of kinetic friction μk = 0.36. The entire time the massless rope used to... 
physics
A block sits against a vertical wall and a 120 lb force P acts diagonally to the left on the block at an angle below the horizontal. Determine the magnitude and direction of the friction force which the vertical wall exerts on the 100 lb block if theta is (a)15 degrees (b)30 ... 
College Physics!
Is there any way i can just get these problems set up? I just need help with the steps on how to do it. A box weighing 600 N is pushed along a horizontal floor at a constant velocity with a force of 250 N parallel to the floor. What is the coefficient of Kinetic friction ... 
PHYSICS
A block with a mass of 126 kg is pulled with a horizontal force of F applied across a rough floor. The coefficent of friction between the floor and the block is 0.7. If the block is moving at a constant velocity, what is the magnitude of F applied? F applied = 
math
Two blocks sit on a horizontal surface. They are connected to each other by a massless cord. The block on the left has a mass of 5.1 kg and the block on the right has a mass of 3.0 kg. Another massless cord is attached to the block on the right and pulls that block with a ... 
Physics
Two blocks sit on a horizontal surface. They are connected to each other by a massless cord. The block on the left has a mass of 4.8 kg and the block on the right has a mass of 2.2 kg. Another massless cord is attached to the block on the right and pulls that block with a ... 
physics
A force of magnitude 25Nis directed at an angle of 37 deg above the horizontal moves a 10 Kg block along a horizontal surface at a constant velocity .How much work is done by this force in moaing the block a distance of 15m? 
Physics
A 23 kg suitcase is being pulled by a handle that is at an angle of 22 degrees above the horizontal. If the normal force exerted on the suitcase is 185 N, what is the force applied to the handle? *** Objects NOT on an incline they are being pushed/pulled at an angle along a ... 
Physics
A 2.95 kg block on a horizontal floor is attached to a horizontal spring that is initially compressed 0.0330 m. The spring has force constant 900 N/m. The coefficient of kinetic friction between the floor and the block is 0.42 . The block and spring are released from rest and ... 
physics
A force of 8.7 N is applied to a steel block initally at rest on a horizontal frictionless surface. The force, which is directed at an angle of 30.0o below the horizontal, gives the block a horizontal acceleration of 5.3 m/s2. a) Draw a free body diagram and sum forces. b) ... 
Physics
A 1.5 kg basketball is thrown to the floor. At the moment it first hits the floor, the basketball has a velocity of 6 m/s directed 45° below the horizontal. In contact with the ball for 0.1 seconds, the floor exerts upon the ball a force of 135 N directed 110° above the ... 
Physics
A box has a weight of 120 N and is being pulled across a horizontal floor by a force that has a magnitude of 100 N. The pulling force can point horizontally, or it can point above the horizontal at an angle θ. When the pulling force points horizontally, the kinetic ... 
Physics
A 10kg box is pulled a distance of 100m along a level floor at constant velocity using a force of 40 N at an angle of 35 degrees above the horizontal. If the box is pulled at constant velocity, what is the coefficient of friction between the bottom of the box and the floor? 
force
A 10kg box is pulled along a horizontal surface by a force of 40N applied at a 30° angle above horizontal. The coefficient of kinetic friction is 0.3. Calculate the acceleration 
Physics help pls
Pls help me I have a test tmrw A block with mass 5kg slides along a horizontal floor under the action of a force 20N applied upward at an angle θ to the horizontal. The coefficient of kinetic friction between the block and the floor is μk = 0.4. Find the angle θ... 
Physics
A 17.8 kg block is dragged over a rough, horizontal surface by a constant force of 72.8 newtons acting at an angle of 31.3 degrees above the horizontal. the block is displaced 64.4 m and the coefficient of kinetic friction is 0.239. find the work done by the 72.8 n force. ...