Since 1 yard = 3 feet, then 5 yards = \(\displaystyle{5}×{3}={155}×{3}={15}\) feet. So, the answer is B.

Question

asked 2021-05-09

Choose the complete factorization of \(4x^{2} - 8x - 60\).

a)2(x + 3) (x - 5)

b)\(4(x^{2} - 2x - 15)\)

c)(2x + 6) (2x - 10)

d)4(x + 3) (x - 5)

a)2(x + 3) (x - 5)

b)\(4(x^{2} - 2x - 15)\)

c)(2x + 6) (2x - 10)

d)4(x + 3) (x - 5)

asked 2021-03-30

A long, straight, copper wire with a circular cross-sectional area of \(\displaystyle{2.1}{m}{m}^{{2}}\) carries a current of 16 A. The resistivity of the material is \(\displaystyle{2.0}\times{10}^{{-{8}}}\) Om.

a) What is the uniform electric field in the material?

b) If the current is changing at the rate of 4000 A/s, at whatrate is the electric field in the material changing?

c) What is the displacement current density in the material in part (b)?

d) If the current is changing as in part (b), what is the magnitude of the magnetic field 6.0cm from the center of the wire? Note that both the conduction current and the displacement currentshould be included in the calculation of B. Is the contribution from the displacement current significant?

a) What is the uniform electric field in the material?

b) If the current is changing at the rate of 4000 A/s, at whatrate is the electric field in the material changing?

c) What is the displacement current density in the material in part (b)?

d) If the current is changing as in part (b), what is the magnitude of the magnetic field 6.0cm from the center of the wire? Note that both the conduction current and the displacement currentshould be included in the calculation of B. Is the contribution from the displacement current significant?

asked 2021-04-13

As depicted in the applet, Albertine finds herself in a very odd contraption. She sits in a reclining chair, in front of a large, compressed spring. The spring is compressed 5.00 m from its equilibrium position, and a glass sits 19.8m from her outstretched foot.

a)Assuming that Albertine's mass is 60.0kg , what is \(\displaystyle\mu_{{k}}\), the coefficient of kinetic friction between the chair and the waxed floor? Use \(\displaystyle{g}={9.80}\frac{{m}}{{s}^{{2}}}\) for the magnitude of the acceleration due to gravity. Assume that the value of k found in Part A has three significant figures. Note that if you did not assume that k has three significant figures, it would be impossible to get three significant figures for \(\displaystyle\mu_{{k}}\), since the length scale along the bottom of the applet does not allow you to measure distances to that accuracy with different values of k.

a)Assuming that Albertine's mass is 60.0kg , what is \(\displaystyle\mu_{{k}}\), the coefficient of kinetic friction between the chair and the waxed floor? Use \(\displaystyle{g}={9.80}\frac{{m}}{{s}^{{2}}}\) for the magnitude of the acceleration due to gravity. Assume that the value of k found in Part A has three significant figures. Note that if you did not assume that k has three significant figures, it would be impossible to get three significant figures for \(\displaystyle\mu_{{k}}\), since the length scale along the bottom of the applet does not allow you to measure distances to that accuracy with different values of k.

asked 2021-02-21

A 15.0 kg block is dragged over a rough, horizontal surface by a70.0 N force acting at 20.0 degree angle above the horizontal. The block is displaced 5.0 m, and the coefficient of kinetic friction is 0.3. Find the work done on the block by ; a) the 70.0 N force,b) the normal force, and c) the gravitational force. d) what is the increase in the internal energy of the block-surface system due to friction? e) find the total change in the kinetic energy of the block.

asked 2021-03-12

A 75.0-kg man steps off a platform 3.10 m above the ground. Hekeeps his legs straight as he falls, but at the moment his feettouch the ground his knees begin to bend, and, treated as aparticle, he moves an additional 0.60 m before coming torest.

a) what is the speed at the instant his feet touch theground?

b) treating him as a particle, what is his acceleration(magnitude and direction) as he slows down, if the acceleration isassumed to be constant?

c) draw his free-body diagram (see section 4.6). in termsof forces on the diagram, what is the net force on him? usenewton's laws and the results of part (b) to calculate the averageforce his feet exert on the ground while he slows down. expressthis force in newtons and also as a multiple of his weight.

a) what is the speed at the instant his feet touch theground?

b) treating him as a particle, what is his acceleration(magnitude and direction) as he slows down, if the acceleration isassumed to be constant?

c) draw his free-body diagram (see section 4.6). in termsof forces on the diagram, what is the net force on him? usenewton's laws and the results of part (b) to calculate the averageforce his feet exert on the ground while he slows down. expressthis force in newtons and also as a multiple of his weight.

asked 2021-04-23

A swimmer wears a heavy belt to make her average densityexactly equal to the density of water. Her mass, includingthe belt, is 60 kg. (a) What is the swimmer's weight innewtons? (b) What is the swimmers volume in m3? (c) At a depth of 2m below the surface ofa pond, what bouyant force acts on the swimmer? Whatnet force acts on her?

asked 2021-05-13

A rectangular barge, 5 m long and 2 m wide, floats in freshwater.

a. Find how much deeper it floatswhen its load is a 400 kg horse.

b. If the barge can only be pushed15 cm deeper into the water before water overflows tosink it, how many 400 kg horses can it carry?

a. Find how much deeper it floatswhen its load is a 400 kg horse.

b. If the barge can only be pushed15 cm deeper into the water before water overflows tosink it, how many 400 kg horses can it carry?

asked 2021-03-24

A 2.4-kg object is attached to a horizontal spring of forceconstant k=4.5 kN/m. The spring is stretched 10 cm fromequilibrium and released. Find (a) the frequency of themotion, (b) the period, (c) the amplitude, (d) the maximum speed,and (e) the maximum acceleration. (f) When does the objectfirst reach its equilibrium position? What is itsacceleration at this time?

Two identical blocks placed one on top of the other rest on africtionless horizontal air track. The lower block isattached to a spring of spring constant k= 600 N/m. Whendisplaced slightly from its equilibrium position, the systemoscillates with a frequency of 1.8 Hz. When the amplitude ofoscillation exceeds 5 cm, the upper block starts to slide relativeto the lower one. (a) What are the masses of the twoblocks? (b) What is the coefficient of static frictionbetween the two blocks?

Two identical blocks placed one on top of the other rest on africtionless horizontal air track. The lower block isattached to a spring of spring constant k= 600 N/m. Whendisplaced slightly from its equilibrium position, the systemoscillates with a frequency of 1.8 Hz. When the amplitude ofoscillation exceeds 5 cm, the upper block starts to slide relativeto the lower one. (a) What are the masses of the twoblocks? (b) What is the coefficient of static frictionbetween the two blocks?

asked 2021-04-24

The following is an 8051 instruction: CJNE A, # 'Q' ,AHEAD

a) what is the opcode for this instruction?

b) how many bytes long is this instruction?

c) explain the purpose of each byte of this instruction.

d) how many machine cycles are required to execute this instruction?

e) If an 8051 is operating from a 10 MHz crystal, how longdoes this instruction take to execute?

a) what is the opcode for this instruction?

b) how many bytes long is this instruction?

c) explain the purpose of each byte of this instruction.

d) how many machine cycles are required to execute this instruction?

e) If an 8051 is operating from a 10 MHz crystal, how longdoes this instruction take to execute?

asked 2020-12-24

At top speed, a coyote can run at a speed
of 44 miles per hour. If a coyote could
maintain its top speed, how far could it run
in 15 minutes?

(A) 2.93 miles

(B) 11 miles

C 176 miles

(D) 660 miles :

(A) 2.93 miles

(B) 11 miles

C 176 miles

(D) 660 miles :