Friday

February 27, 2015

February 27, 2015

Total # Posts: 63

**math Please HElp**

The minute hand on a watch is 7 mm long and the hour hand is 4 mm long. How fast is the distance between the tips of the hands changing at one o'clock? (Round your answer to one decimal place.)
*February 26, 2013*

**calculus 1**

Differentiate. f(x) = 8 − x^ex/x + ex f '(x) =
*February 8, 2013*

**Significant digits**

round 799.9696 to 4 significant figures
*February 6, 2013*

**math**

round 799.9696 to 4 significant figures
*February 6, 2013*

**calculus 1**

particle moves along a straight line with equation of motion s = f(t), where s is measured in meters and t in seconds. Find the velocity and speed when t = 6. (Round your answers to two decimal places.) f(t) = t−1 − t velocity m/s speed m/s
*January 31, 2013*

**calculus 1**

If f(x) = 9x2 − x3, find f'(2) and use it to find an equation of the tangent line to the curve y = 9x2 − x3 at the point (2, 28).
*January 31, 2013*

**physics**

The total cross-sectional area of the load-bearing calcified portion of the two forearm bones (radius and ulna) is approximately 2.0 cm2. During a car crash, the forearm is slammed against the dashboard. The arm comes to rest from an initial speed of 80 km/h in 5.0 ms. If the ...
*January 26, 2013*

**physics**

(a) Calculate the mass flow rate (in grams per second) of blood (ρ = 1.0 g/cm3) in an aorta with a cross-sectional area of 2.0 cm2 if the flow speed is 35 cm/s. g/s (b) Assume that the aorta branches to form a large number of capillaries with a combined cross-sectional ...
*January 26, 2013*

**physics**

Water flowing through a garden hose of diameter 2.73 cm fills a 25.0-L bucket in 1.20 min. (a) What is the speed of the water leaving the end of the hose? m/s (b) A nozzle is now attached to the end of the hose. If the nozzle diameter is one-third the diameter of the hose, ...
*January 26, 2013*

**physics**

A small ferryboat is 4.00 m wide and 6.00 m long. When a loaded truck pulls onto it, the boat sinks an additional 4.50 cm into the river. What is the weight of the truck?
*January 26, 2013*

**calculus 1**

Evaluate the limit limit t^4 − 625/t^3 − 125 t → 5
*January 22, 2013*

**trigonometry**

Prove cotx-1/cotx+1=1-sin2x/cos2x
*December 9, 2012*

**physics**

A car is designed to get its energy from a rotating flywheel (solid disk) with a radius of 1.00 m and a mass of 600 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 4,000 rev/min. (a) Find the kinetic ...
*November 30, 2012*

**physics**

A horizontal 790-N merry-go-round of radius 1.30 m is started from rest by a constant horizontal force of 50 N applied tangentially to the merry-go-round. Find the kinetic energy of the merry-go-round after 2.0 s. (Assume it is a solid cylinder.) J
*November 30, 2012*

**physics**

A 280-N sphere 0.20 m in radius rolls without slipping 6.0 m down a ramp that is inclined at 25° with the horizontal. What is the angular speed of the sphere at the bottom of the slope if it starts from rest? rad/s
*November 30, 2012*

**trigonometry**

The sprockets and chain of a bicycle are shown in the figure. The pedal sprocket has a radius of 4 in., the wheel sprocket a radius of 2 in., and the wheel a radius of 13 in. The cyclist pedals at 45 rpm. (a) Find the angular speed of the wheel sprocket. rad/min (b) Find the ...
*November 29, 2012*

**trigonometry**

A truck with 48-in.-diameter wheels is traveling at 45 mi/h. (a) Find the angular speed of the wheels in rad/min. rad/min (b) How many revolutions per minute do the wheels make? rev/min
*November 26, 2012*

**trigonometry**

The wheels of a car have radius 11 in. and are rotating at 800 rpm. Find the speed of the car in mi/h. mi/h
*November 26, 2012*

**physics**

An electric motor rotating a workshop grinding wheel at a rate of 9.80 101 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 2.00 rad/s2. (a) How long does it take for the grinding wheel to stop? s (b) Through how many radians ...
*November 14, 2012*

**physics**

A dentist's drill starts from rest. After 2.50 s of constant angular acceleration it turns at a rate of 3.0 104 rev/min. (a) Find the drill's angular acceleration. rad/s2 (b) Determine the angle (in radians) through which the drill rotates during this period. rad
*November 14, 2012*

**physics**

Use the data of this table to find the point between Earth and the Sun at which an object can be placed so that the net gravitational force exerted by Earth and Sun on this object is zero.
*November 14, 2012*

**physics**

It has been suggested that rotating cylinders about 12 mi long and 4.1 mi in diameter be placed in space and used as colonies. What angular speed must such a cylinder have so that the centripetal acceleration at its surface equals the free-fall acceleration on Earth?
*November 14, 2012*

**math**

Find an equation for the ellipse that satisfies the given conditions. Length of major axis 6, length of minor axis 4, foci on y-axis
*November 10, 2012*

**physics**

A skier starts from rest at the top of a hill that is inclined at 9.5° with respect to the horizontal. The hillside is 225 m long, and the coefficient of friction between snow and skis is 0.0750. At the bottom of the hill, the snow is level and the coefficient of friction ...
*October 12, 2012*

**physics**

A block of mass 2.50 kg is pushed 2.80 m along a frictionless horizontal table by a constant 12.0 N force directed 25.0° below the horizontal. (a) Determine the work done by the applied force. J (b) Determine the work done by the normal force exerted by the table. J (c) ...
*October 12, 2012*

**physics**

A 650-kg elevator starts from rest and moves upward for 2.80 s with constant acceleration until it reaches its cruising speed, 1.64 m/s. (a) What is the average power of the elevator motor during this period? W (b) How does this amount of power compare with its power during an...
*October 12, 2012*

**physics**

A skier of mass 74 kg is pulled up a slope by a motor-driven cable. (a) How much work is required to pull him 90 m up a 30° slope (assumed frictionless) at a constant speed of 3.0 m/s? J (b) What power (expressed in hp) must a motor have to perform this task? hp
*October 12, 2012*

**physics**

A skier starts from rest at the top of a hill that is inclined at 9.5° with respect to the horizontal. The hillside is 225 m long, and the coefficient of friction between snow and skis is 0.0750. At the bottom of the hill, the snow is level and the coefficient of friction ...
*October 12, 2012*

**physics**

Hooke's law describes a certain light spring of unstretched length 32.0 cm. When one end is attached to the top of a door frame and a 5.40-kg object is hung from the other end, the length of the spring is 46.5 cm. (a) Find its spring constant. kN/m (b) The load and the ...
*October 12, 2012*

**physics**

A 2.1 103-kg car starts from rest at the top of a 5.9-m-long driveway that is inclined at 19° with the horizontal. If an average friction force of 4.0 103 N impedes the motion, find the speed of the car at the bottom of the driveway. m/s
*October 12, 2012*

**physics**

A 52-kg pole vaulter running at 12 m/s vaults over the bar. Her speed when she is above the bar is 0.7 m/s. Neglect air resistance, as well as any energy absorbed by the pole, and determine her altitude as she crosses the bar.
*October 12, 2012*

**physics**

Tarzan swings on a 34.0-m-long vine initially inclined at an angle of 33.0° with the vertical. (a) What is his speed at the bottom of the swing if he starts from rest? m/s (b) What is his speed at the bottom of the swing if he pushes off with a speed of 5.00 m/s? m/s
*October 10, 2012*

**physics**

A 7.80-g bullet moving at 520 m/s penetrates a tree trunk to a depth of 4.60 cm. (a) Use work and energy considerations to find the average frictional force that stops the bullet. N (b) Assuming the frictional force is constant, determine how much time elapses between the ...
*October 10, 2012*

**physics**

A block of mass 2.50 kg is pushed 2.80 m along a frictionless horizontal table by a constant 12.0 N force directed 25.0° below the horizontal. (a) Determine the work done by the applied force. J (b) Determine the work done by the normal force exerted by the table. J (c) ...
*October 10, 2012*

**college algebra**

(x+2)(x^2-2x+4)(x-2)(x^2+2x+4)
*October 5, 2012*

**math**

The volume of a cone is 190 in3. Find a function that models the height h of the cone in terms of its radius r.
*October 5, 2012*

**math**

A right triangle has one leg four times as long as the other. Find a function that models its perimeter P in terms of the length x of the shorter leg.
*October 5, 2012*

**math**

The sum of two positive numbers is 90. Find a function that models their product P in terms of x, one of the numbers.
*October 5, 2012*

**math**

A rectangle has an area of 15 m2. Find a function that models its perimeter P in terms of the length x of one of its sides.
*October 5, 2012*

**math**

The height of a cylinder is three times its radius. Find a function that models the volume V of the cylinder in terms of its radius r.
*October 5, 2012*

**math**

A poster is 12 inches longer than it is wide. Find a function that models its area A in terms of its width w.
*October 5, 2012*

**physics**

A 3.00-kg block starts from rest at the top of a 27.5° incline and slides 2.00 m down the incline in 1.20 s. (a) Find the acceleration of the block. m/s2 (b) Find the coefficient of kinetic friction between the block and the incline. (c) Find the frictional force acting on...
*October 2, 2012*

**physics**

A 1,080-N crate is being pushed across a level floor at a constant speed by a force of 290 N at an angle of 20.0° below the horizontal, as shown in the figure (a) below. (a) What is the coefficient of kinetic friction between the crate and the floor? (b) If the 290-N force...
*October 2, 2012*

**physics**

A dockworker loading crates on a ship finds that a 21-kg crate, initially at rest on a horizontal surface, requires a 70-N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 51 N is required to keep it moving with a constant ...
*October 2, 2012*

**ALGEBRA**

Find the amount of compound interest earned in an account that opens with $29,000, earns 7.5% interest compounded daily, and is held for 5 years. Assume 360 days in a year. (Round your answer to the nearest cent.)
*May 19, 2012*

**ALGEBRA**

If $835 is invested in an account that earns annual interest of 4.5%, compounded semiannually, what will the account balance be after 13 years? (Round your answer to the nearest cent.)
*May 19, 2012*

**ALGEBRA**

Determine the comparable interest rate for a $80,000 loan when the quoted information is 12.1% + 0.5 pt + $300. (Round your answer to two decimal places.)
*May 18, 2012*

**ALGEBRA**

Calculate the monthly finance charge for the following credit card transaction. Assume that it takes 10 days for a payment to be received and recorded and that the month is 30 days long. Assume 365 days in a year. (Round your answer to the nearest cent.) $3,000 balance, 21% ...
*May 18, 2012*

**ALGEBRA**

Find the APR for the following loan (monthly payments). (Round your answer to the nearest full percent.) Purchase a refrigerator for $2,100 at 20% add-on interest for 3 years.
*May 18, 2012*

**ALGEBRA**

If $695 is invested in an account that earns 21.75%, compounded annually, what will the account balance be after 15 years? (Round your answer to the nearest c
*May 18, 2012*

**ALGEBRA**

Find the future value, using the future value formula and a calculator. (Give your answer to the nearest cent.) $44.01 at 6.5% compounded semiannually for 2 years
*May 18, 2012*

**ALGEBRA**

Calculate the monthly finance charge for the following credit card transaction. Assume that it takes 10 days for a payment to be received and recorded and that the month is 30 days long. (Round your answer to the nearest cent.) $300 balance, 18% rate, $250 payment, previous ...
*May 17, 2012*

**ALGEBRA**

Many states offer personalized license plates. California, for example, allows personalized plates with seven spaces for numerals or letters, or one of the following four symbols. What is the total number of license plates possible using this counting scheme? (Assume that each...
*May 16, 2012*

**ALGEBRA**

A certain lock has three tumblers, and each tumbler can assume seven positions. How many different possibilities are there?
*May 16, 2012*

**ALGEBRA**

From a survey of 100 college students, a marketing research company found that 70 students owned iPhones, 30 owned cars, and 15 owned both cars and iPhones. (a) How many students owned either a car or an iPhone (but not both)? students (b) How many students do not own either a...
*May 16, 2012*

**ALGEBRA**

a) What is the sum of the first 70 consecutive odd numbers? Tell whether it illustrates inductive or deductive reasoning. inductive reasoning deductive reasoning What is the sum of the first 1,400 consecutive odd numbers? Tell whether it illustrates inductive or deductive ...
*May 16, 2012*

**ALGEBRA**

Give the numbers of elements in the regions marked I, II, III, IV, V, VI, VII, VIII in the figure. |U| = 220, |A| = 20, |B| = 14, |C| = 12 |A∩B| = 2, |A∩C| = 2, |B∩C| = 6, |A∩B∩C| = 1 | I | = | II | = | III | = | IV | = | V | = | VI | = | VII...
*May 11, 2012*

**ALGEBRA**

A poll was taken of 100 students at a commuter campus to find out how they got to campus. The results are below. 57 said they drove alone. 29 rode in a carpool. 30 rode public transportation. 6 used both carpools and public transportation. 9 used both a carpool and sometimes ...
*May 10, 2012*

**ALGEBRA**

In a recent survey of 100 women, the following information was gathered. 36 use shampoo A. 37 use shampoo B. 38 use shampoo C. 14 use shampoos A and B. 8 use shampoos A and C. 9 use shampoos B and C. 3 use all three. Use the figure to answer the question in the problem. How ...
*May 10, 2012*

**ALGEBRA**

In a recent survey of 100 women, the following information was gathered. 36 use shampoo A. 46 use shampoo B. 37 use shampoo C. 19 use shampoos A and B. 11 use shampoos A and C. 10 use shampoos B and C. 9 use all three. How many are using shampoos A and C, but not B (Region IV)?
*May 10, 2012*

**socail**

T/F 1.Socialist feminism combines radical and Marxist principles in explaining the nature and causes of crime.
*December 6, 2009*

**social**

T/F 1.Marxist feminists emphasize that class is secondary to the concept of gender in their analyses of crime in a sexist capitalist society.
*December 6, 2009*

**Algebra**

Factor completely. 6z3 – 27z2 + 12z State which method should be applied as the first step for factoring the polynomial.
*May 13, 2007*

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