The pressure exerted by a phonograph needle on a record is surprisingly large. If the equivalent of 1.00 g is supported by a needle, the tip of which is a circle 0.200 mm in radius, what pressure is exerted on the record in N/m2?

  1. 👍
  2. 👎
  3. 👁
  1. p=F/A= mg/πr²=
    =0.001/3.14•0.0002²=7958 Pa

    1. 👍
    2. 👎
  2. 7937

    1. 👍
    2. 👎
  3. Elana almost got it right
    =0.001/(3.14*(0.0002)^2)=7961.78 or 7962 Pa

    1. 👍
    2. 👎
  4. pressure is force/Area, in this case, your force is the weight of the needle (remember to take gravity into account) F = .001 * 9.8. Your needle tip has a radius of .002m and the area of a circle is A= pir^2 = 3.14(.002)^2. Your final equation should look like this Pressure = (.001 * 9.8)/(3.14(.002)^2)

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    A hypodermic syringe contains a medicine with the density of water (figure below). The barrel of the syringe has a cross-sectional area of 2.44 10-5 m2. In the absence of a force on the plunger, the pressure everywhere is 1.00

  2. algebra

    According to Boyle’s law, the volume V of a gas varies inversely to the pressure P exerted by the gas. The volume of a given gas under a pressure of 32 kg per cm2 is 200 cm3. What will be the volume of this gas when the pressure

  3. physics

    The voltage across a membrane forming a cell wall is 80.0 mV and the membrane is 8.80 nm thick. What is the electric field strength? (The value is surprisingly large, but correct. Membranes are discussed in Section 19.7* of the

  4. math

    the needle of the scale in bulk food section of a supermarket is 25 cm long. find the distance when the needle rotates 50 degrees

  1. physics

    A hypodermic needle consists of a plunger of circular cross-section that slides inside a hollow cylindrical syringe. When the plunger is pushed, the contents of the syringe are forced through a hollow needle (also of circular

  2. math

    p=14.63⋅0.8 Atmospheric pressure, measured in pounds per square inch p, s, i is the force exerted by Earth's atmosphere over a given area. The atmospheric pressure, p, exerted on an airplane flying at an altitude of a miles

  3. Physics

    A person of weight 820 N stands on one leg. The area of the foot in contact with the floor is 1.4 X 10^-2 m^2 a. Calculate the pressure exerted by the foot on the ground. b. Explain what would happen to the pressure exerted on the

  4. math

    Find the pressure exerted by the atmosphere on a car window which is 30 cm tall and 40 cm wide if atmospheric pressure is 101,000 Pa. (Remember that a Pa = N/m2)

  1. science

    A 2.5L flask contains 0.25mol each of so2 and n2 gas at 27 ° c. calculate the partial pressure exerted by each gas and also the total pressure exerted by each gas and the total pressure. name the law on which it is based

  2. AP Physics

    The volume of liquid flowing per second is called the volume flow rate "Q" and has the dimensions of [L]^3/[T]. The flow rate of a liquid through a hypodermic needle during an injection can be estimated with the following

  3. college chemistry

    calculate the pressure exerted by 2.50 moles of CO2 confined in a volume of 5.00 L at 450K. Compare the pressure with that predicted by the ideal gas equation.

  4. Re post water in tanks problem

    A./_\ B.\_/ C.|_| The three tanks shown above are filled with water to an equal depth. All the tanks have an equal height. Tank A has the greatest surface area at the bottom, tank B the least and tank C the middle. (Select T-True,

You can view more similar questions or ask a new question.