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2 years ago

A cell membrane has a thickness of about 7 nm. How many cell membranes would it take to make a stack 3.4 in high?

Physics

1 answer:

sergiy2304 [10]2 years ago

3 0

Answer:

486 of cell membranes

Explanation:

one cell membrane has 7*10^-9m as the height

So, by dividing 3.4 with 7*10^-9 you will get the number of cell require to form the height.

3.4/(7*10^-9)=485.71

because we can't have decimal number of cell we would round it into three significant figures, 486.

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How much is 1.75 inches in cm?

saul85 [17]

Answer:

4.44 cm

Explanation:

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3 years ago

Read 2 more answers

A car of 900 kg mass is moving at the velocity of 60 km/hr. It is brought into rest at 50 meter distance by applying a brake. No

kozerog [31]

Answer: $-2502N$

Explanation:

$(V_2)^2=(V_1)^2+2ad$

where;

$V_2$ = final velocity = 0

$V_1$ = initial velocity = 60 km/h = 16.67 m/s

$a$ = acceleration

$d$ = distance

First all of, because acceleration is given in m/s and not km/h, you need to convert 60km/h to m/s. Our conversion factors here are 1km = 1000m and 1h = 3600s

$60km/h(\frac{1000m}{1km} )(\frac{1h}{3600s} )=16.67m/s$

Solve for a;

$(V_2)^2=(V_1)^2+2ad$

Begin by subtracting $(V_1)^2$

$(V_2)^2-(V_1)^2=2ad$

Divide by 2d

$\frac{(V_2)^2-(V_1)^2}{2d} =a$

Now plug in your values:

$a=\frac{(0)^2-(16.67 m/s)^2}{2(50m)}$

$a=\frac{0-277.89m^2/s^2}{100m}$

$a=-2.78m/s$

If you're wondering why I calculated acceleration first is because in order to find force, we need 2 things: mass and acceleration.

$F=ma$

m = mass = 900kg

a = acceleration = -2.78m/s

$F=(900kg)(-2.78m/s)\\F=-2502N$

It's negative because the force has to be applied in the opposite direction that the car is moving.

8 0

2 years ago

he drag characteristics of a torpedo are to be studied in a water tunnel using a 1 : 7 scale model. The tunnel operates with fre

dusya [7]

Answer:20.03 m/s

Explanation:

Given

$L_r=1:7$

velocity of Prototype $v_p=53 m/s$

Taking Froude number same for both flow as it is a dimensionless number for different flow regimes in open Flow

$(\frac{v_m}{\sqrt{L_mg}})=(\frac{v_p}{\sqrt{L_pg}})$

$v_m=v_p\times \sqrt{\frac{L_m}{L_p}}$

$v_m=53\times \frac{1}{\sqrt{7}}$

$v_m=20.03 m/s$

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2 years ago

Choose the correct statement concerning electrical circuits. A) The electrons in a circuit move from the positive to the negativ

zavuch27 [327]

Answer: C

Explanation:

when more volts are in a battery the more current you receive.

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2 years ago

A basketball player can jump upwards with a velocity of 3m/s. How long is she in the air before coming back to the ground? I nee

Mamont248 [21]

In this problem, we have an initial velocity $v_{i}=3m/s$ jump upwards (opposite direction to gravity) with the acceleration due to gravity $g=-9.8m/s^2$ , finally the player will reach to final velocity in the air $v_{f}$

Using the equation of motion, the third equation states that:

$v_{f}^{2} =v_{i} ^{2}+2gh$

where h is the height , the distance which the player reach in air

Thus

$0^{2} =3 ^{2}+2*(-9.8)*h$

$h=\frac{3^2}{2*9.8}= \frac{9}{19.6}= 0.459m$

4 0

2 years ago