1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
dezoksy [38]
2 years ago
14

The ball of a ballpoint pen is 0.5 mm in diameter and has an ASTM grain size of 12. How many grainsare there in the ball

Physics
1 answer:
Alina [70]2 years ago
5 0

Answer:

the number of grains in the ball is 274,848

Explanation:

Given that;

diameter = 0.5 mm

so radius r = 0.25 mm

first we determine the volume of the ball using the following equation;

V = 4/3×πr³

we substitute

V = 4/3×π(0.25)³

V =  0.06544 mm³

Now form table 1.1 "Grain sizes" a metal with grain size number of 12 has about 4,200,000 grains/mm³

so;

Number of grains N = 0.06544 × 4,200,000

N = 274,848 grains

Therefore, the number of grains in the ball is 274,848

You might be interested in
I.Name two commonly used thermometric liquids.
PtichkaEL [24]

Answer:

mercury and alcohol

ii) used to test temperatures

6 0
3 years ago
Read 2 more answers
A hot-water bottle contains 787 g of water at 75∘C. If the liquid water cools to body temperature (37 ∘C), how many kilojoules o
IgorC [24]

Answer:

Q = 787 gr * 1 \frac{cal}{gr C} *(37-75)C = -29906 cal

So then the answer for this case would be 29906 cal but we need to convert this into KJ and we know that 1 cal = 4.184 J and if we convert we got:

29906 cal *\frac{4.184 J}{1 cal}* \frac{1KJ}{1000 J}= 125.127 KJ

Explanation:

For this case we know the mass of the water given :

m = 787 gr

And we know that the initial temperature for this water is T_i =75 C.

We want to cool this water to the human body temperature T_f = 37 C

Since the temperatures given are not near to 0C (fusion point) or 100C (the boling point) we don't need to use latent heat, then the only heat involved for this case is the sensible heat given by:

Q= m c_p \Delta T

Where c_p represent the specific heat for the water and this value from tables we know that c_p =1 \frac{cal}{gr C} for the water.

So then we have everything in order to replace into the formula of sensible heat and we got:

Q = 787 gr * 1 \frac{cal}{gr C} *(37-75)C = -29906 cal

So then the answer for this case would be 29906 cal but we need to convert this into KJ and we know that 1 cal = 4.184 J and if we convert we got:

29906 cal *\frac{4.184 J}{1 cal}* \frac{1KJ}{1000 J}= 125.127 KJ

8 0
3 years ago
Read 2 more answers
If the earth shrank until its radius were only one-quarter its present size without changing its mass what would a 20 n object w
Dahasolnce [82]

Basing on the information given, we can calculate the new weight of the object by the following given:current weight = 20 Ng = 10m/s2

20N/4 = 5N

Thank you for your question. Please don't hesitate to ask in Brainly your queries. 
5 0
3 years ago
A 7300 kg rocket blasts off vertically from the launch pad with a constant upward acceleration of 2.20 m/s2 and feels no appreci
Simora [160]

Answer:

Explanation:

We shall first calculate the velocity at height h = 575 m .

acceleration a = 2.2 m /s²

v² = u² + 2 a s

u is initial velocity , v is final velocity , s is height achieved

v² = 0 + 2 x 2.2 x 575

v = 50.3 m /s

After 575 m , rocket moves under free fall so g will act on it downwards

If it travels further by height H

from the relation

v² = u² - 2 g H

v = 0 , u = 50.3 m /s

H = ?

0 = 50.3² - 2 x 9.8 H

H = 129.08 m

Total height attained by rocket

= 575 + 129.08

= 704.08 m .

4 0
2 years ago
anonymous 4 years ago The turbidity levels of water in four locations are shown in the table below. Which of these conclusions i
Tresset [83]
Hello!

The Correct Answer would 100% be:

Option "C".

"People in location C would complain about foul taste in water".

I Hope my answer has come to your Help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead! :)

(Mark As Brainliest IF Helped!)

-TheOneAboveAll :D
4 0
3 years ago
Read 2 more answers
Other questions:
  • The rate at which energy is transferred
    8·2 answers
  • In figure (10), an experiment is set up to find out which metal is the best conductor of heat. Balls are stuck with wax to rods
    13·2 answers
  • Legal concept establishing that evidence speaks for itself
    15·1 answer
  • A baseball goes from zero to 34 m/s in 0.188 s. What is its average acceleration? Answer in units of m/s^2
    15·1 answer
  • An object is in uniform circular motion, tracing an angel at 30 degrees every 0.010 seconds. What's the period of this motion an
    12·1 answer
  • You have been training and can run a mile in 6.5 minutes. How long would it take to run a lap around the outside track, which is
    9·1 answer
  • g The current through a 10 m long wire has a current density of 4 cross times 10 to the power of 6 space open parentheses bevell
    5·1 answer
  • 5.00 kg of liquid water is heated to 100.0 °C in a closed system. At this temperature, the density of liquid water is 958 kg/m3
    12·1 answer
  • What is the MAJOR IMPORTANT difference between velocity and speed?
    5·2 answers
  • A 30-g bullet traveling horizontally at 300 m/s strikes a 1.0-kg block which is attached to a horizontal spring with a force con
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!