Newton's law of motion Questions and Answers

In the system shown below, the coefficient of static friction between the block and the table is 0.60. The coefficient of kinetic friction is 0.40. i) What mass of the hanging block will start the system moving? ii) Once it is moving, what is the acceleration?

A crane is lifting a large crate to the top of a building. If the tension on the wire in the crane is 9870 N and the angle the crane makes with the ground is 37.90, what is the component of the tension that lifts the crate? Please show your work for full credit.

Blocks with masses of 2.0 kg, 3.0 kg, and 6.0 kg are lined up in a row on a frictionless table. All three are pushed forward by a 60 N force applied to the 2.0 kg block. Part A How much force does the 3.0 kg block exert on the 6.0 kg block? Express your answer with the appropriate units. HA Part B Value Submit Request Answer N ONIO ? How much force does the 3.0 kg block exert on the 2.0 kg block? Express your answer with the appropriate units.

(14%) Problem 7: A block with mass m₂ = 7.2 kg rests on the surface of a horizontal table which 0.69. A second block with a mass m₂ = 11.5 kg is has a coefficient of kinetic friction of u connected to the first by an ideal string passing over an ideal pulley such that the second block is suspended vertically. The second block is released from rest, and motion occurs. Jackson, Dasia-djackson2@ttu.edu

A block with mass m₁ = 7.2 kg rests on the surface of a horizontal table which has a coefficient of kinetic friction of μ = 0.69. A second block with a mass m₂ = 11.5 kg is connected to the first by an ideal string passing over an ideal pulley such that the second block is suspended vertically. The second block is released from rest, and motion occurs. Jackson, Dasin -djackson2 @ltu.edu

To meet a U.S. Postal Service requirement, employees' footwear must have a coefficient of static friction of 0.5 or more on a specified tile surface. A typical athletic shoe has a coefficient of 0.809. In an emergency, what is the minimum time interval in which a person starting from rest can move 3.16 m on a tile surface if she is wearing the following footwear? (a) footwear meeting the Postal Service minimum (b) a typical athletic shoe

When all of the forces acting upon an object balance each other, what will happen to the acceleration of the object? A Increase in acceleration B Decrease in acceleration C No change in acceleration

When you trip, your foot stops, but your body continues to move forward. Which statement best explains why this happens? O The unbalanced force that stops your foot pulls your body forward. O Inertia pushes your body forward after your foot stops. O An unbalanced force pushes your body forward. An unbalanced force stops your foot but does not act on the rest of your body.

The forces in (Eigure 1) act on a 2.8 kg object. Figure 120° 5.0 N 3.0 N 1 of 1 2.82 N 1.0 N Y Part A What is the value of az, the x-component of the object's acceleration? Express your answer with the appropriate units. A₂ = 1.792 Submit ▸ Part B μà Provide Feedback m/s² Previous Answers Request Answer X Incorrect; Try Again; 2 attempts remaining ?

A bowler throws a ball down the lane toward the pins. The ball reaches the pins and slowly moves through them, knocking down the center pins but leaving the end pins standing. The bowler wants the ball to reach all the pins. Which changes should the bowler make so that the ball has a greater acceleration? (1 point) O The bowler should choose a ball with less mass.or throw the ball with less force. O The bowler should choose a ball with less mass or throw the ball with more force. O The bowler should choose a ball with more mass or throw the ball with more force. O The bowler should choose a ball with more mass or throw the ball with less force.

O Car A is traveling at 22.0 m/s and car B at 29.0 m/s. Car A is 300 m behind car B when the driver of car A accelerates his car with a uniform forward acceleration of 2.40 m/s2. How long after car A begins to accelerate does it take car A to overtake car B? HINT: use to obtain a position function for each car. (30 points) x(t)=1/2at²+v+xo

Once you have pulled hard enough to start the box moving upward, what is the magnitude F of the upward force you must apply to the rope to start raising the box with constant velocity?

A 1400 kg steel beam is supported by two ropes. (Figure 1) For help with math skills, you may want to review: Vector Components What is the tension in rope 17 Express your answer with the appropriate units. ▸View Available Hint(s)

The maker of an automobile advertises that it takes 11 seconds to accelerate from 15 kilometers per hour to 70 kilometers per hour. Assuming constant acceleration, compute the following. (a) The acceleration in meters per second per second (Round your answer to three decimal places.) m/sec2 (b) The distance the car travels during the 11 seconds (Round your answer to two decimal places.) m

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. The scale reads 830 N for the first 2.6 s after the elevator starts moving, then 930 N for the next 2.6 s. Y Part A What is the elevator's speed 5.2 s after starting? Express your answer with the appropriate units. U= 11 Part B Value HÅ Submit Request Answer Oupward 3 downward m/s What is the direction of the elevator's velocity 5.2 s after starting? PINO ? Review

Compressed air is used to fire a 52 g ball vertically upward from a 1.2-m-tall tube. The air exerts an upward force of 1.4 N on the ball as long as it is in the tube. Part A How high does the ball go above the top of the tube?

Question is ponty Your golf cart broke down and you are pushing it off the road with a constant firm force in neutral gear. Just as it budged and is accelerating, the force you are applying to the car is the cart does not apply any force to you greater than the force the cart applies back to you less than the force the cart applies back to you O the same as the force the cart applies back to you

A 55.0 kg box hangs from a rope. What is the tension in the rope if: Part C The box has vy = 5.30 m/s and is speeding up at 4.60 m/s²? The y axis points upward. T= Part D The box has v₂ = 5.30 m/s and is slowing down at 4.60 m/s²? Express your answer with the appropriate units.

A string can hold up 15.9 kg without breaking. You tie the string to a 30. kg object sitting on ice and use it to pull the object horizontally for 21.6 m. Calculate the minimum possible time to complete the task. (1 Point) O 15 s O 0.60 s O 2.9 s 8.3 s

Four students are playing a game of tug-of- war. The two students on the right weigh 54 kg and 57 kg, and pull with a combined force of 140 N. The two students on the left weigh 53 kg and 55 kg and pull with a combined force of 120 N. Calculate the magnitude and direction of the acceleration of the students. 1.2 m/s² [right] 0.091 m/s² [right] 1.2 m/s² [left] 0.18 m/s² [right]

8. A 50.0-kg crate is being pulled along a horizontal smooth surface. The pulling force is 10.0 N and is directed 20.0° above the horizontal. What is the magnitude of the acceleration of the crate? O 0.188 m/s² O 0.0684 m/s² O 0.200 m/s² O 0.376 m/s² 0.0728 m/s2

A 12.0 kg monkey starts to climb a long rope to reach a banana located at a height of 7.20 m. The rope will snap if the tension exceeds 132 N. Calculate the least amount of time the monkey could take to reach the banana without breaking the rope. Find the maximum acceleration the monkey can have without breaking the rope. 3.79s

Atwood's Machine An Atwood's machine consists of two masses, m₁ and m2, connected by a string that passes over a pulley. Part A If the pulley is a disk of radius R and mass M, find the acceleration of the masses. Express your answer in terms of the variables m₁, m2, R, M, and appropriate constants. a=

You and your friend Peter are putting new shingles on a roof pitched at 24°. You're sitting on the very top of the roof when Peter, who is on the edge of the roof, 5.4 m away, asks you for the box of nails. Rather than carry the 2.5 kg box of nails down to Peter, you decide to give the box a push and have it slide down to him. If the coefficient of kinetic friction between the box and the roof is 0.50, with what speed should you push the box to have it gently come to rest right at the edge of the roof?

Zach, whose mass is 84 kg, is in an elevator descending at 9 m/s. The elevator takes 2.5 s to brake to a stop at the first floor. What is Zach's weight before the elevator starts braking? Express your answer with the appropriate units. What is Zach's weight while the elevator is braking?

A diver climbs up the stairs to the diving tower. The work he does climbing the stairs is: 1.half his kinetic energy just as he hits the water 2.equal to his kinetic energy just as he hits the water 3.half his potential energy just as he hits the water 4.equal to his potential energy just as he has the water

Which provides the most Ideal Mechanical Advantage? a. A four-meter-long ramp, 3 meters tall b. A six-meter-long ramp, 3 meters tall c. A twelve-meter-long ramp, 6 meters tall d. A twelve-meter-long ramp, 3 meters tall

A brave but inadequate rugby player is being pushed backward by an opposing player who is exerting a force of 800 N on him. The mass of the losing player plus equipment is 90.0 kg, and he is accelerating at 1.20 m/s² backward. (a) What is the force of friction between the losing player's feet and the grass? (b) What force does the winning player exert on the ground to move forward if his mass plus equipment is 110 kg? (c)Draw a sketch of the situation showing the system of interest used to solve each part. For this situation, draw a free-body diagram and write the net force equation.

A 328-kg car moving at 19.1 m/s in the +x direction hits from behind a second car moving at 13.0 m/s in the same direction. If the second car has a mass of 790 kg and a speed of 15.1 m/s right after the collision, what is the velocity of the first car after this sudden collision? a.18.2 m/s b. -14.0 m/s c.14.0 m/s d. 24.2 m/s

A pitcher throws a 0.19-kg baseball ball with a velocity of 42 m/s. It is struck by the bat with an average force of 700 N, which results in a velocity of 28 m/s in the opposite direction from the original velocity. How long were the bat and ball were in contact?

Aaron stands on a scale which is set on floor tilted at 15° to the horizontal. The scale reads zero. more than his true weight. less than the normal force from the scale on him. his true weight. less than his true weight.

In researching the forces that act on flying birds, scientists studied the motion of cockatiels' bodies as they fly in horizontal flight. As the birds beat their wings, their bodies move up and down. (Figure 1) shows the vertical acceleration of a cockatiel's body during one wing beat, consisting of an upstroke followed by a downstroke.

Jason works for a moving company. A 35 kg wooden crate is sitting on the wooden ramp of his truck; the ramp is angled at 11°.

The trap-jaw ant, found throughout tropical South America, catches its prey by very rapidly closing its mandibles around its victim. (Figure 1) shows the speed of one of its mandible jaws versus time in microseconds.

5.0 kg wood block is on ice being pulled by two equal forces of 20 Newtons applied at the same point. The angle between the forces is 120 degrees. Find the acceleration of the block, neglect friction.

An object has a kinetic energy of 273 J and a momentum of magnitude 20.0 kg . m/s. (a) Find the speed of the object. m/s (b) Find the mass of the object. kg

A 1500-kg car traveling east with a speed of 25.0 m/s collides at an intersection with a 2500-kg van traveling north at a speed of 20.0 m/s. Find the direction and magnitude of the velocity of the wreckage after the collision, assuming that the vehicles undergo a perfectly inelastic collision (i.e. they stick together).

1. A railroad car of mass 2.50-10 kg is moving at a speed of 4.00 m/s. It collides and couples with three other coupled railroad cars, each of the same mass as the single car and moving in the same direction with an initial speed of 2.00 m/s. (a) What is the speed of the four cars after the collision? (b) How much energy is lost in the collision? Where does this energy go?

A rifle with a weight of 25 N fires a 5.3-g bullet with a speed of 200 m/s. (a) Find the recoil speed of the rifle. m/s (b) If a 725-N man holds the rifle firmly against his shoulder, find the recoil speed of the man and rifle. m/s

A 67-kg pole vaulter running at 11 m/s vaults over the bar. Her speed when she is above the bar is 1.4 m/s. Neglect air resistance, as well as any energy absorbed by the pole, and determine her altitude as she crosses the bar

A mechanic pushes a 3.50 x 10³-kg car from rest to a speed of v, doing 5,340 J of work in the process. During this time, the car moves 26.0 m. Neglecting friction between car and road, find v and the horizontal force exerted on the car.

A dockworker loading crates on a ship finds that a 32-kg crate, initially at rest on a horizontal surface, requires a 74-N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 52 N is required to keep it moving with a constant speed. Find the coefficients of static and kinetic friction between crate and floor.

How much force does an 89 kg astronaut exert on his chair while sitting at rest on the launch pad? Express your answer in newtons. How much force does the astronaut exert on his chair while accelerating straight up at 14 m/s² ? Express your answer in newtons. N

A baseball player catches a ball of mass 100 grams which is moving with a speed of 10 m/s in 0.2 seconds. What is the amount of force exerted by him? 5N 0 N 10 N 1 N

A construction worker is standing on a metal beam supported by two vertical cables. The uniform beam weighs 624 N and is 3.1 m long. The cables are located at opposite ends of the beam. What is the tension each cable when the 960-N worker stands 1.10 m from one end? (Hints: It does not matter which end you place the construction worker closer to. Either way one cable is under a greater tension.) smaller tension larger tension

A 2300 kg truck has put its front bumper against the rear bumper of a 2500 kg SUV to give it a push. With the engine at full power and good tires on good pavement, the maximum forward force on the truck is 18,000 N. Part A What is the maximum possible acceleration the truck can give the SUV? Express your answer with the appropriate units. α= At this acceleration, what is the force of the SUV's bumper on the truck's bumper? Express your answer with the appropriate units. FSUV on truck=

Corey, whose mass is 95 kg, stands on a bathroom scale in an elevator. The scale reads 860 N for the first 3.0 s after the elevator starts to move, then 930 N for the next 3.0 s. What is the elevator's velocity 6.0 s after starting?

Blocks with masses of 1.0 kg, 2.0 kg, and 3.0 kg are lined up in a row on a frictionless table. All three are pushed forward by a 16 N force applied to the 1.0 kg block. Part A How much force does the 2.0 kg block exert on the 3.0 kg block? Express your answer with the appropriate units. F2.0 on 3.0 = Part B How much force does the 2.0 kg block exert on the 1.0 kg block? Express your answer with the appropriate units. F2.0 on 1.0 =

Which Newton's law describes action and reaction? First law Second law Third law Law of gravitation

(a) A person is pulling on a 10.0-kg box with a force of 40.0 N directed at horizontally. Will the person be successful in pulling the box if the coefficient of static friction is 0.500? (b) The person is now pulling with a force of 40.0 N directed at 30.0° with respect to the horizontal. If the coefficient of kinetic friction is 0.250, what is the acceleration of the box? (c) What happens if the person is pulling with the force of 200. N directed at 30.0° with respect to the horizontal? Draw an FBD to justify your answer.