# Posts by martin

Total # Posts: 220

**Physics**

A body vibrates in simple harmonic motion with an amplitude of 5 cm and a frequency of 0.50 Hz. a) Calculate: i) the maximum acceleration ii) the maximum velocity iii) the magnitude of the acceleration and velocity when the body is displaced 10 mm from its equilibrium position...

**Physics**

The piston in a particular car engine moves in approximately simple harmonic motion with an amplitude of 8 cm. The mass of the piston is 8 kg and the piston makes 100 oscillations per second. Calculate: a) the maximum value if the acceleration of the piston. b) the force ...

**Physics**

a) A 40 cm radius wheel is rotating at 20rad/sec. How fast is this wheel moving across the ground? b) How far (in meters) will this wheel move in 6 seconds?

**Physics**

a) Find the angular velocity of a wheel that rotates 6 times every 4 seconds. b) What is the tangential velocity of the outside of the wheel if the radius is 15 cm?

**Physics**

a) Find the angular velocity of a 40 cm radius wheel that is moving at 20 m/s. b) How many times will this wheel rotate in 5 seconds?

**Maths **

A father was three times as old as his son fifteen years ago and four times his sons age nineteen years ago. When was the father twice as old as the son?

**philosophy**

1.Only claims that can be objectively verified can be trusted. 2.Many people have reported encounters with ghosts. 3. So the existence of ghosts is likely to be true. 1. acceptable by observation 2. acceptable by testimony 3. unacceptable by testimony I was asked to state the ...

**Physics**

A driver jumps off the 3.0m diving board with an initial velocity of 5.0m/s. (a) Determine the maximum height, (b) The time to reach the maximum height, (c) The time it took to touch the water, and (c) The speed when touching the water.

**Math (Pre algebra )**

368 gallons / 32 miles per gallon = 11.5 gallons

**Maths**

Solve Simultaneous Equetion Using Elimination Method: (A)2x - 3y= -3 and 3x - 7y= -1.

**Chem**

A student mixed 6 g of ice at -3.4 degrees celsius with 1 g of steam at 103 degrees celsius. What was the final temperature of this mixture.i tried equalling mcdelta T. Please help asap. I would be eternally grateful. Please answer in kj or J only

**Chem**

A student mixed 6 g of ice at -3.4 degrees celsius with 1 g of steam at 103 degrees celsius. What was the final temperature of this mixture.i tried equalling mcdelta T. Please help asap. I would be eternally grateful

**Science**

A snooker ball X of mass 0.3kg moving at 5m/s hit a stationary ball Y of mass 0.4kg and Y move at a velocity of 2m/s at angle to the initial direction of X. Find the velocity and direction of X after hitting

**Algebra**

The ratio of the areas of two squares is 32/63. After rationalizing the denominator, the ratio of their side lengths can be expressed in the simplified form (a*sqrt b)/c where a, b, and c are integers. What is the value of the sum a + b + c?

**Life orientation**

Six ways

**school of the nation**

Marie gets $500 pocket money each day,she spends $300 each day. Write fractions to show the money spent and money left: (1) at the end of 1 day (2) at the end of 1 week

**physics**

hf=hi+1/2 g t^2 + vit hf, hi=0 t= 2vi/g horizontal distance= t*17.5m/s

**statistics**

4. The Graduate Record Exam (GRE) has a combined verbal and quantitative mean of 1000 and a standard deviation of 200. Scores range from 200 to 1600 and are approximately normally distributed. For each of the following problems: (a) draw a rough sketch, darkening in the ...

**algebra A055,**

World Records in the 1500-m Run. The formula R = -0.075t + 3.85 can be used to predict the world record in the 1500-m run t years after 1930. Determine (in terms of an inequality) those years for which the world record will be less than 3.5 min. { Y l Y > 1930 } ?

**algebra A055,**

World Records in the 1500-m Run. The formula R = -0.075t + 3.85 can be used to predict the world record in the 1500-m run t years after 1930. Determine (in terms of an inequality) those years for which the world record will be less than 3.5 min. { Y l Y > 1930 } ?

**algebra**

World Records in the 1500-m Run. The formula R = -0.075t + 3.85 can be used to predict the world record in the 1500-m run t years after 1930. Determine (in terms of an inequality) those years for which the world record will be less than 3.5 min.

**History :)**

Civil Rights

**History :)**

Can someone help with this one please? Select one reform movement from the Progressive Era. Describe the movement and its impact on South Carolina. Provide details and examples that support how this movement changed South Carolina. Websites and examples will help! Thanks! :)

**Science**

I think they should measure the temperature

**modern physics**

a hunter on the ground fires a bullet in the northeast direction which strikes a deer 0.25 metre away from him, the bullet travel with a speed of 1800m/hr.at the instant an airplane is directly over the hunter at an altitude of one metre and is traveling due east with a ...

**Political Science**

States’ rights to regulate may not trample on powers specifically reserved for Congress. 100% right

**Political Science**

In Gibbons v. Ogden, the Supreme Court held that?

**Political Science**

No state may distinguish between gay marriage and heterosexual marriage because that would effectively create invidious distinctions. This is 100% answer

**Political Science**

If the Supreme Court were to rule that gay marriage is a fundamental right, under the Equal Protection Clause of the Fourteenth Amendment, that would mean?

**Political Science**

In Marbury v. Madison, the Supreme Court established the principle of constitutional review by? I am seconding guessing myself on my answer so can you point me the right direction is it: claiming that Section 13 of the 1789 Judiciary Act providing that the Supreme Court will ...

**Math**

What is the greatest common factor of 32 and 40? the answer is 8

**Political Science**

The states’ rights supersede national authority. Right

**Political Science**

In Gibbons v. Ogden, the Supreme Court held that? In Chapter 7 Federal Authority and the Limits to State Authority. If I am understanding right that the 10th Amendment trumps the Interstate Commerce Clause. I am I right?

**Chemistry**

What is the molarity of 35.0 of NaCl in 125 mL of water?

**phsics**

a man weighs 1370N on earth what would he weigh on jupiter where free fall acceleration is 25.9 m/s2 the acceleration of gravity is 9.8 m/s2 in units of N

**Chem**

Solid urea, (NH2)2CO, burns to give CO2,N2, and liquid H2O. Its heat of combustion is -632.2 kJ/mol. Balance the equation for combustion of urea, and calculate the heat generated per mole of H2O formed. (Enter in kJ.)

**physics**

A 2.40 kg firecracker explodes into two pieces and produces 170 J of heat, light, and sound energy. One of the pieces has a mass of 0.800 kg and a speed of 4.50 m/s after the explosion. If the mass of the other piece is 1.20 kg, what is its speed after the explosion?

**algebra 1**

24 gallons

**physics**

4140

**math**

Don't know

**Math**

would it be negative 17?

**Math**

Write an integer that is represented by the bold words in the following sentence. The temperature dropped 17 degrees between noon and midnight.

**functions**

What is the rule for input 0 output -1

**Math**

An investment was worth $1000. By the end of 2010 the investment had lost 30%. What percent must the investment grow by in 2011 to be worth $1000 by the end of 2011? Round your answer to the nearest tenth of a percent.

**Math**

7.99 meters or 8.01 meters

**History**

What would Jackie Robinson (might) accomplish as president of USA

**Physics**

Yep, 8*10*-6 is the answer. A square loop of wire of side L with total resistance R moves at constant speed v into a region of uniform magnetic field B pointing perpendicular to the plane of the loop. What is the average current that is induced. Iave=BL^2/R is that the answer???

**english**

2. Tecumseh's "Let the white race perish" speech is A. a logical list of reasons why the whites should be resisted. B. a satire on the white race and its traditions. C. a plea to the people's reason. D. an appeal to the emotions of his listeners.

**COMM100**

Which of the following would be an appropriate way to use the DECIDE tool in response to research suggesting that there are differences between the way men and women communicate?

**Math**

The number N of state and federal inmates in millions during year x, where x>2002 can be approximated by the following formula N=0.04x-79.02

**Physics**

A race car starts from rest in the pit area and accelerates at a uniform rate to a speed of 35 m/s in 11s, moving on a circular track of radius 500 m. Determine the tangential and centripetal components of the net force excreted on the car(by the ground) when it's speed is...

**Physics 1**

I'm sorry when it's speed is 15 m/s. doesn't say uniform

**Physics 1**

(I) determine the tangential and centripetal components of the net force excreted on the car(by the ground) when it accelerates at a uniform speed of 15 m/s in 11 s, moving on a circular track of radius 500m. The cars mass is 1100kg.

**Physics 1**

(I) determine the tangential and centripetal components of the net force excreted on the car(by the ground) when it accelerates at a uniform speed of 15 m/s in 11 s, moving on a circular track of radius 500m. The cars mass is 1100kg.

**Math/ Calculus Help1**

Supplies are dropped from a stationary (not moving up or down) helicopter and, after some amount of time, land on the ground with a velocity of -160 feet per second. Assumptions: Start time at t = 0 and ignore air resistance. Recall that the height function is given by y(t)= ...

**CHEM**

Yes, I can use the Ka of HClO. (hypochlorite ion from hypochlorous) HClO is a weak acid with a Ka of 2.9*10-8 The pKa = 7.54 (-log of the Ka) Since the concentration ratio is equal to 1 and the log of 1 is zero, the pH would equal the pKa. Please verify

**CHEM**

How can I calculate a pH of hypochlorite buffer into LiCLO with only initial concentrations and no Ka value? [CLO-]=.1M [LiCLO]=.1M

**math**

what would 1.25 be as a fraction?

**math**

can you divide a fraction into another fraction?

**English paper 3**

Write a dialogue in wich you convince your teacher that you are too sick to participate in sports for thed day

**English paper 3**

An discursive essay of this topic , both parrents should assume equal responsibility in raising a child,agree or dis agree

**Sciience**

Do you know what is qualitative data?Please help me

**POL 201**

Under the War Powers Act, the President? 1)may never use force unless Congress first authorizes it. Answer 2)may in effect fight a 90 day war without a declaration from Congress. 3)can act unilaterally in matters of military action. 4)gives over control of “police ...

**Math help please!!**

Given: angle A is 20˚, b = 50 cm, for what possible range of lengths of side “a” would triangle ABC have two possible solutions (approximate to 2 decimal places)?

**MATH HELP!!!**

Given: A is 20˚, b = 50 cm, for what possible range of lengths of side “a” would ABC have two possible solutions (approximate to 2 decimal places)?

**chemistry**

Is 39.2 in KJ/mol? please help

**science**

please drwls, what is the answer of a and b

**chemistry**

50 g Si doped with 27g Sb

**Chemistry**

1KJ/mol=1.03*10^-2EV please somebody tell about b

**Chemistry**

somebody please tell the answer of b. I tried with all equation. D=D0e^-Ea/RT Created Eq.1 for 35+273K and Eq.2 for 45+273k i got Ea 1.55*10^4J/mol even after conversion with j/mol to EV not getting green check 1KJ/mol=1.03*10^-2 if some body got green check please suggest me.

**Chemistry**

what would be answer of b. would it be 45

**Chemistry**

someone please help regarding answer of a and b. 18 is not showing green check

**Chemistry**

rufus, please what is answer

**Chemistry**

chacho,could you please explain the answer when de broglie wavelength 0.468*10^-10m.

**chemistry**

1ev= 1.69*10^-19 J

**chemistry**

39.2 is wrong answer. could you please help for the answer of b

**Chemistry**

could any one help me regarding correct answer of this question

**Chemistry**

Anonymous, could you please explain the answer. the answer you mentioned is wrong

**math**

If you borrow $15,000 from your dad for college and you agree to pay him $25,000 back at 8% compound interest per year. How many years do you think you have to do this? In other words, given the amounts and the interest rate, what is the number of years?

**Percentage**

The usual price of a suitcase was $100. During a sale, a 13% discount was given. Mr Lee bought the suitcase but had to pay 7% GST on the selling price. a.) What was the selling price of the suitcase? b.) How much did Mr Lee pay for the suitcase?

**AP Chemistry**

If 15.0mL of 2.50M NaCl is mixed with 60.0mL of 0.300M Pb(NO3)2, what is the mass of the precipitate

**MATH**

Use a table of trigonometric values to find the angle è in the right triangle in the following problem. Round to the nearest degree, if necessary. cos è=? A=22 H=38

**chemistry**

Hvap 40.65 kJ/mol Hf -285.83 kJ/mol Hfusion 6.03 kJ/mol specific heat 4.186 J/gC molar mass 18.02 g How much energy is consumed by thawing 4.3 g ice?

**chemistry**

Hvap 40.65 kJ/mol Hf -285.83 kJ/mol Hfusion 6.03 kJ/mol specific heat 4.186 J/gC molar mass 18.02 g How much energy is consumed by thawing 4.3 g ice?

**physics**

given that the mass of an electron is 9.1 x 10^-28 grams and the charge on an electron is 1.6 x 10^-19 Coulombs, calculate the voltage required to lift an electron 5 cm. the question was previously answered, but I did'nt understand it .. could some show me again please.

**physics**

Hi Damon .. where did the 10^-3 come from? .. I understand the 9.8 is gravity and the 5 is 5 cm

**physics**

Given that the mass of an electron is 9.1 x 10^-28 grams and the charge on an electron is 1.6 x 10^-19 Coulombs, calculate the voltage required to lift an electron 5 cm. not quite sure how to do this.

**physics 30**

A flash of lightning transfers 1.5 x 10^9 Joules of energy through a potential difference of 5.0 x 10^7 Volts between a cloud and the ground. Calculate the quantity of charge transferred in the lightning bolt. How many electrons were transferred? Does this get easier? I hope so.

**Physics 30**

Hello damon... I'm not sure what happened there... what happened to the 5.0 x 10^-6 Could you show me again, as I don't quite understand it. thanks martin

**Physics 30**

A test charge of 5.0x10^-6 C is moved 2.0 cm through an electric force of 6.0 x 10^-7 N . What is the change in evergy of the test charge? What is the change in voltage on the charge? Help

**science**

how does the moon move through space ?

**Math**

3x2x4

**math**

write three ways to find 3x2x4

**physics**

Consider a system of N identical particles. Each particle has two energy levels: a ground state with energy 0, and an upper level with energy . The upper level is four-fold degenerate (i.e., there are four excited states with the same energy ). (a) Write down the ...

**math**

solve the system 7x^2 - 5y^2 + 20y = 3 21x^2 + 5y^2 =209

**mechanics**

Two 20kg weights are hung from light strings that pass over frictionless pulleys. The ends of the strings are connected to a small, light spring balance, S, calibrated in kg. The pulley axes are mounted on the wall of a lift in a 50-storey building. What is the reading on the ...

**Basic Statistics**

In each of the following situations state whether or not the given assignment of probabilities to individual outcomes is legitimate, that is, satisfies the rules of probability. If not, give a reason a) roll a die and record the count of spots on the up-face P(1)=0 P(2)=1/6 P(...

**geometry**

A ball gas a radius of 56mm (a)Calculate the surface area (b)What is the volume of the sphere

**psy230**

don't know

**Arithmetic**

Given the sequence Tq=-7+3(q+4) find T4,and x if Tx=50.