azmen asked in Science & MathematicsPhysics · 9 years ago

# If 1 inch is equal to 2.5 cm, approximately how many inches are in 1000 kilometers?

-If 1 inch is equal to 2.5 cm, approximately how many inches are in 1000 kilometers?

-If a man is 6 foot 4 inches tall, what is his approximate height in centimeters? (1 in. = 2.54 cm)

-The terminal velocity of a drop of water falling through the atmosphere is v = (2/9) (r2 g p/n) where v is the velocity of the drop in m/s; r is the radius of the drop in m; g is the acceleration of gravity in m/s2 and p is the density of water in kg/m3. What must be the units of n, the coefficient of viscosity of the air through which the drop falls?

Relevance
• DaveWH
Lv 7
9 years ago

OK.

1 inch = 2.5 cm = 2.5 / 100 m = 0.025m = 0.025 / 1000 km = 0.000025 km

So in 1000 km we have = 1000 / 0.000025 = 40 000 000 inches

1 inch = 2.5 cm

12 inches = 1ft = 12 * 2.5 = 30 cm

6 ft 4 inches = (6 * 30) +(4 * 2.5) = 180 + 10 = 190 cm

For your last bit we have

v = (2/9) ( r^2 g p / n)

n = (2/9) ( r^2 g p / v)

When working out units, you can ignore any dimensionless constants. So we can forget about the (2/9)

Let me now rewrite n in terms of the units of the other quantities. We should see that some of them will cancel out.

v = m/s

r^2 = m^2

g = m / t^2

p = kg / m^3

n = (m^2) (m / t^2) (kg / m^3) (t / m)

n = kg / (mt)

So the units read 'kg per meter per second' which sounds right for a viscosity.

• Anonymous
5 years ago

RE:

If 1 inch is equal to 2.5 cm, approximately how many inches are in 1000 kilometers?

-If 1 inch is equal to 2.5 cm, approximately how many inches are in 1000 kilometers?

-If a man is 6 foot 4 inches tall, what is his approximate height in centimeters? (1 in. = 2.54 cm)

-The terminal velocity of a drop of water falling through the atmosphere is v = (2/9) (r2 g p/n) where v...

Source(s): 1 equal 2 5 cm approximately inches 1000 kilometers: https://tr.im/rp7Lj
• 9 years ago

so 100cms are in a meter, and 1000 meters are in a kilometer. so first figure out how many cm's are in a km. which is 100x1000 which is 100,000. take that and divide by 2.5 cause that's how many cms are in an inch which give you 40,000 inches in a kilometer.

fore the second one you convert the feet into inches.. so you have 6x12 which is 72 plus the 4inchs and it's 76... then take that 76x the 2.54 and you have 193.04cms

the answer to the last question is most likely m2/s... i looked it up and found it through wiki

Kinematic viscosity is the dynamic viscosity divided by the density (typical units m2/s, Stokes, St)

• 3 years ago

1 Inch Is How Many Cm

• 9 years ago

for the first answer don't forget that in the question there are 1000 kilometers, which is 1000 x 1000 x 100 cms. I make it 40,000,000 in

the last one is just dimentional analysis, write out all the units of the terms in the equation and cancel:

[m]/[s] = [m]^2 x [m]/[s]^2 x [kg]/[m]^3 x 1/[n]

cancelling and rearranging...

n = [kg]/[m][s] so the units of n are kg per m per s