0.075 L - 9 mL = ____________

5. The most dangerous place to use electrical equipment is?

podryga [215]

C) because you could get hurt if certain items fall in it and you are in water

7 0

3 years ago

Neon has 10 protons and 10 electrons. How many additional electrons would it take to fill the outer (second) electron shell?

blondinia [14]

The first shell has 2 in and the second shell has 8 in therefore ypuvwont need to add anymore :-) so the answer is 0

6 0

3 years ago

Read 2 more answers

When you drop a 0.43 kg apple, Earth ex erts a force on it that accelerates it at 9.8m / (s ^ 2) toward the earth's surface. Acc

Sever21 [200]

Answer:

The answer to the question is highlighted in the box

8 0

1 year ago

A mail carrier leaves the post ofﬁce and drives 2.00 km to the north. He then drives in a direction 60.0° south of east for 7.00

Oxana [17]

Answer:

12.97 km

Explanation:

In order to find the resultant displacement, we have to resolve each of the 3 displacements along the x and y direction.

Taking north as positive y direction and east as positive x-direction, we have:

- Displacement 1: 2.00 km to the north

So

$A_x = 0\\A_y = +2.00 km$

- Displacement 2: 60.0° south of east for 7.00 km

So

$B_x=(7.00)(cos (-45^{\circ}))=4.95 km\\B_y = (7.00)(sin (-45^{\circ}))=-4.95 km$

- Displacement 3: 9.50 km 35.0° north of east

So

$C_x=(9.50)(cos 35^{\circ})=7.78 km\\C_y=(9.50)(sin 35^{\circ})=5.45 km$

So the net displacement along the two directions is:

$R_x=A_x+B_x+C_x=0+4.95+7.78=12.73 km\\R_y=A_y+B_y+C_y=2.00+(-4.95)+5.45=2.50 km$

So, the distance between the initial and final position is equal to the magnitude of the net displacement:

$R=\sqrt{R_x^2+R_y^2}=\sqrt{12.73^2+2.50^2}=12.97 km$

7 0

3 years ago

A barrel 1 m tall and 60 cm in diameter is filled to the top with water. What is the pressure it exerts on the floor beneath it?

allsm [11]

Answer:

The pressure on the ground is about 9779.5 Pascal.

The pressure can be reduced by distributing the weight over a larger area using, for example, a thin plate with an area larger than the circular area of the barrel's bottom side. See more details further below.

Explanation:

Start with the formula for pressure

(pressure P) = (Force F) / (Area A)

In order to determine the pressure the barrel exerts on the floor area, we need the calculate the its weight first

$F_g = m \cdot g$

where m is the mass of the barrel and g the gravitational acceleration. We can estimate this mass using the volume of a cylinder with radius 30 cm and height 1m, the density of the water, and the assumption that the container mass is negligible:

$V = h\pi r^2=1m \cdot \pi\cdot 0.3^2 m^2\approx 0.283m^3$

The density of water is 997 kg/m^3, so the mass of the barrel is:

$m = V\cdot \rho = 0.283 m^3 \cdot 997 \frac{kg}{m^3}= 282.151kg$

and so the weight is

$F_g = 282.151kg\cdot 9.8\frac{m}{s^2}=2765.08N$

and so the pressure is

$P = \frac{F}{A} = \frac{F}{\pi r^2}= \frac{2765.08N}{\pi \cdot 0.3^2 m^2}\approx 9779.5 Pa$

This answers the first part of the question.

The second part of the question asks for ways to reduce the above pressure without changing the amount of water. Since the pressure is directly proportional to the weight (determined by the water) and indirectly proportional to the area, changing the area offers itself here. Specifically, we could insert a thin plate (of negligible additional weight) to spread the weight of the barrel over a larger area. Alternatively, the barrel could be reshaped (if this is allowed) into one with a larger diameter (and smaller height), which would achieve a reduction of the pressure.

7 0

3 years ago

0.075 L - 9 mL = _____________ L?