The heaviest invertebrate is the giant squid, which is estimated to have a weight of about0.15tons spread out over its length of30feet.What is its weight in newtons? N

2.

[0.17/1 Points]DETAILSPREVIOUS ANSWERSSERCP11 4.2.P.004.

MY NOTES

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One or more external forces are exerted on each object enclosed in a dashed box shown in the figures below. Identify the reaction to each of these forces. (Assume that (a), (b) and (c) occur on Earth while (d), (e) and (f) occur far from any outside gravitational influences. Select all that apply.)Six figures each show an arrow, representing a force, acting on an object, where the object is outlined in a dashed box. Figures (a) - (c) show contact forces. Figures (d) - (f) show field forces.

• Figure (a): A horizontal spring attached at its left end to a wall. A hand is pulling the spring from its right end toward the right. An arrow points to the right above the hand. The spring is enclosed in a dashed box.
• Figure (b): A woman pulling a wagon pull cart toward the right, with a child sitting in the wagon. An arrow points diagonally up and right from the wagon to the pull handle. The cart and child are enclosed in a dashed box.
• Figure (c): A football player kicking a ball up and left at an angle. An arrow is shown to point at that angle up and left away from the ball. The ball is enclosed in a dashed box.
• Figure (d): A small ball of massmmoving toward the right toward a large ball of massM. An arrow points to the right from the small ball toward the bigger ball. The small ball is enclosed in a dashed box.
• Figure (e): A small ball of chargeqmoving toward the right toward a large ball of charge +Q. An arrow points to the right from the small ball toward the bigger ball. The small ball is enclosed in a dashed box.
• Figure (f): A small iron block moving toward the right toward a rectangular magnet. The magnet's left and right ends are labeled "N" and "S", respectively. An arrow points to the right from the iron block toward the magnet. The iron block is enclosed in a dashed box.

(a) the spring exerts a force

to the left on the handto the right on the wallto the right on the handdownward on the Earthto the left on the wallupward on the Earth

(b) the wagon exerts a force

upward to the left on the handledownward to the left on the handledownward on the Earth due to gravitational attractionupward on the Earth due to gravitational attractionupward on the Earth due to contactdownward on the Earth due to contact

(c) the ball exerts a force

downward to the left on the playerdownward on the Earthupward to the right on the playerupward on the Earthdownward to the right on the player

(d)mexerts a force

to the left onMdownward onMupward onMto the right onM

(e)qexerts a force

downward onQto the left onQupward onQto the right onQ

(f) the iron exerts a force

to the right on the magnetupward on the magnetto the left on the magnetdownward on the magnet

3.

[0.5/1 Points]DETAILSPREVIOUS ANSWERSSERCP11 4.2.P.007.

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Four forces act on an object, given by

A=40.3N east,

B=39.3N north,

C=74.7N west,

and

D=92.7N south.

(Assume east and north are directed along the+x-axisand+y-axis,respectively.)

HINT

(a)

What is the magnitude of the net force (in N) on the object?

N

(b)

What is the direction of the force? (Enter your answer in degrees counterclockwise from the +x-axis.)

Always remember to check a vector's quadrant when finding its direction using the inverse tangent function. On most calculators, the

tan¹

function returns the correct angle only when the vector lies in the first or forth quadrant. When it lies in the second or third quadrant, 180must be added to the calculator's answer.counterclockwise from the +x-axis

4.

[-/1 Points]DETAILSSERCP11 4.2.P.010.

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A4.0-g bullet leaves the muzzle of a rifle with a speed of338m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the0.84-m-longbarrel of the rifle? N

5.

[-/1 Points]DETAILSSERCP11 4.2.P.017.

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A force of25.0N is applied in the positivex-direction to a block of mass5.45kg, at rest on a frictionless surface.

HINT

(a)

What is the block's acceleration (in m/s²)? (Indicate the direction with the sign of your answer.)

m/s²

(b)

How fast is it going (in m/s) after2.00s?

m/s

6.

[-/1 Points]DETAILSSERCP11 4.2.P.018.

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What would be the acceleration of gravity (in m/s²) at the surface of a world withfour timesEarth's mass andfive timesits radius?

HINT

m/s²

7.

[-/1 Points]DETAILSSERCP11 4.3.P.019.

MY NOTES

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Calculate the magnitude of the normal force on a12.7kg block in the following circumstances. (Enter your answers in N.)

HINT

(a)

The block is resting on a level surface.

N

(b)

The block is resting on a surface tilted up at a40.8angle with respect to the horizontal.

N

(c)

The block is resting on the floor of an elevator that is acceleratingupwardat2.28m/s².

N

(d)

The block is on a level surface and a force of115N is exerted on it at an angle of40.8belowthe horizontal.

N

8.

[-/1 Points]DETAILSSERCP11 4.3.P.022.

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A student of mass63.4kg, starting at rest, slides down a slide17.2m long, tilted at an angle of32.1with respect to the horizontal. If the coefficient of kinetic friction between the student and the slide is0.133, find the force of kinetic friction, the acceleration, and the speed she is traveling when she reaches the bottom of the slide. (Enter the magnitudes.)

HINT

(a)

the force of kinetic friction (in N)

N

(b)

the acceleration (in m/s²)

m/s²

(c)

the speed she is traveling (in m/s)

m/s

9.

[-/1 Points]DETAILSSERCP11 4.3.P.025.

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A rocket takes off from Earth's surface, accelerating straight up at41.2m/s². Calculate the normal force (in N) acting on an astronaut of mass88.4kg, including his space suit. (Assume the rocket's initial motion parallel to the+y-direction.Indicate the direction with the sign of your answer.)

HINT

N

10.

[-/1 Points]DETAILSSERCP11 4.4.P.027.

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Amuleis harnessed to a sled having a mass of256kg, including supplies. Themulemust exert a force exceeding1180N at an angle of30.3(above the horizontal) in order to get the sled moving. Treat the sled as a point particle.

HINT

(a)

Calculate the normal force (in N) on the sled when the magnitude of the applied force is1180N. (Enter the magnitude.)

N

(b)

Find the coefficient of static friction between the sled and the ground beneath it.

(c)

Find the static friction force (in N) when themuleis exerting a force of5.9010²Non the sled at the same angle. (Enter the magnitude.)

N

11.

[-/1 Points]DETAILSSERCP11 4.4.P.030.

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Suppose the coefficient of static friction between aquarterand the back wall of a rocket car is0.267. At what minimum rate (in m/s²) would the car have to accelerate so that aquarterplaced on the back wall would remain in place?

HINT

m/s²

12.

[-/1 Points]DETAILSSERCP11 4.5.P.032.

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Two identical strings making an angle of=30.3with respect to the vertical support a block of massm=22.2kg(see the figure below). What is the tension in each of the strings? (Enter your answer in N.)

HINT

An illustration shows a block of massmsuspended from a ceiling by two strings of equal length. The lower ends of the strings share a single anchor point at the center of the block's upper surface while their upper ends have separate anchor points along the ceiling. Each string forms an anglewith the vertical.

N

13.

[-/1 Points]DETAILSSERCP11 4.6.P.040.

MY NOTES

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The leg and cast in the figure below weigh365N (w₁). Determine the weightw₂and the angleneeded so that no force is exerted on the hip joint by the leg plus cast.

w2	= N
	=

An illustration shows a side view of a patient laid on their back as their leg, wrapped in a cast, is elevated by a system of two pulleys, two objects, and two cords.

• The pulleys are anchored to the ceiling and positioned such that the first pulley (to the left) is above the foot of the bed while the second pulley (to the right) is above the patient's chest.
• An arrow labeledw₁extends vertically downward from a point near the middle of the elevated leg.
• One end of the first cord is attached at the tail of arroww₁while the other end of the cord is attached to an object of 110 N. The cord forms a clockwise angle of 40above the horizontal before passing over the first pulley and suspending the 110-N object.
• One end of the second cord is also attached to the tail of arroww₁while the other end of the cord is attached to an object labeledw₂. The cord forms a counterclockwise angleabove the horizontal before passing over the second pulley and suspending objectw₂.

14.

[-/1 Points]DETAILSSERCP11 4.6.P.048.

MY NOTES

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A block of mass18.2kg is sliding at an initial velocity of5.65m/s in the positivex-direction. The surface has a coefficient of kinetic friction of0.193. (Indicate the direction with the signs of your answers.)

HINT

(a)

What is the force of kinetic friction (in N) acting on the block?

N

(b)

What is the block's acceleration (in m/s²)?

m/s²

(c)

How far will it slide (in m) before coming to rest?

m

15.

[-/1 Points]DETAILSSERCP11 4.6.P.053.

MY NOTES

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A setup similar to the one shown in the figure below is often used in hospitals to support and apply a traction force to an injured leg.

Figure

An illustration shows a horizontal leg attached to a complex pulley system comprised of four pulleys, an 8.00 kg block, and a long rope. Refer to the adjacent description for more details.

Description

(a) Determine the force of tension in the rope supporting the leg. N (b) What is the traction force exerted on the leg? Assume the traction force is horizontal. N

16.

[-/1 Points]DETAILSSERCP11 4.7.P.054.

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An Atwood's machine (see the figure below) consists of two masses: one of mass4.33kg and the other of mass11.1kg.When released from rest, what is the acceleration of the system? (Enter the magnitude inm/s².)

HINT

A string passes over a pulley which is suspended from a horizontal surface. A circular object of massm₁and a rectangular object of massm₂are, respectively, attached to the left and right ends of the string. An arrow labeled vectora₁beside the circular object points upward while another arrow also labeled vectora₂is beside the rectangular object and points downward.

m/s²

17.

[-/1 Points]DETAILSSERCP11 4.7.P.055.

MY NOTES

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A block of massm₁=14.4kgis on a frictionless table to the left of a second block of massm₂=16.7kg,attached by a horizontal string (see the figure below).

HINT

Two masses,m₁andm₂, are placed on a horizontal surface such that they do not touch andm₁is to the left ofm₂. The left and right ends of a string are, respectively, attached tom₁andm₂. A horizontal rightward arrow labeled vectorFextends fromm₂.

(a)

If a horizontal force of1.1310²Nis exerted on the blockm₂in the positivex-direction, use the system approach to find the acceleration (in m/s²) of the two blocks.

m/s²

(b)

What is the tension (in N) in the string connecting the blocks?

N

18.

[-/1 Points]DETAILSSERCP11 4.7.P.065.MI.

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Objects with massesm₁=11.0kg andm₂=8.0kg are connected by a light string that passes over a frictionless pulley as in the figure below. If, when the system starts from rest,m₂falls 1.00 m in1.55s, determine the coefficient of kinetic friction betweenm₁and the table. An illustration shows a rectangular block of massm₁on the horizontal surface of a table. This is connected to another rectangular block of massm₂by a cord that runs over a pulley placed diagonally at the corner of the horizontal surface of the table. The rectangular block of massm₂is suspended vertically by the side of the tabletop.

19.

[-/1 Points]DETAILSSERCP11 4.A.P.075.

MY NOTES

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Consider the figure below.A traffic light is suspended from a horizontal surface by two cables, each of which makes an angle of 45.0with the horizontal. An arrow labeled 60.0 N points from the top of the traffic light along each cable.

(a) What is the resultant force exerted by the two cables supporting the traffic light in the figure?

magnitude	N
direction	---Select--- rightward downward upward leftward

(b) What is the weight of the light? N

20.

[-/1 Points]DETAILSSERCP11 4.A.P.081.MI.

MY NOTES

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A frictionless plane is 10.0 m long and inclined at41.0. A sled starts at the bottom with an initial speed of5.80m/s up the incline. When the sled reaches the point at which it momentarily stops, a second sled is released from the top of the incline with an initial speedv_i. Both sleds reach the bottom of the incline at the same moment.(a) Determine the distance that the first sled traveled up the incline. m (b) Determine the initial speed of the second sled. m/s