1. What is the chemical name of the following chemical symbols?<br> Be<br> Nel<br> Mg<br> Na

A radio station tower was built in two sections. From a point 87 feet from the base of the tower, the angle of elevation of the

Fiesta28 [93]

Answer:

tan theta = H / B where H is height of triangle and B the length of base

H1 = 87 * tan 25 = 40.6 feet

H2 = 87 * tan 40 = 73 feet

H2 - H1 = 32.4 feet

3 0

3 years ago

5. An undisturbed soil sample has a wet density of 2.5 Mg/m3 when the water content is 25%. The specific gravity of the soil par

Dima020 [189]

Answer:

The submerged effective density is 86.93 kN/m³ or 8.693 Mg/m³

Explanation:

Given;

wet density of soil sample = 2.5 Mg/m³ = 25 kN/m³

Specific gravity of solid particle = 2.7

The dry unit weight of soil;

$\gamma _d = \frac{\gamma _t}{1 +w} = \frac{25}{1+0.25} = 20 \ kN/m^3$

for undisturbed state, the volume of the soil is;

$V_s =\frac{\gamma _d}{G_s \gamma _w} = \frac{20}{2.7*9.81} = 0.76 \ m^3\\\\Void \ volume, V_v = 1-0.76 = 0.24 \ m^3$

$Void \ ratio, \ e = \frac{0.24}{0.76} = 0.32$

Submerged effective density is given as;

$\rho _b = \frac{\rho_w(\gamma_s -1)}{1+e}$

density of water (ρw) = 2.7 x 25 kN/m³ = 67.5 kN/m³, substitute this in the above equation;

$\rho _b = \frac{\rho_w(\gamma_s -1)}{1+e} = \frac{67.5(2.7 -1)}{1+0.32} = 86.93 \ kN/m^3$

Therefore, the submerged effective density is 86.93 kN/m³ or 8.693 Mg/m³

5 0

3 years ago

What is the full moon that occurs during the autumn equinox called?

zhannawk [14.2K]

Answer: Harvest Moon

Explanation:

But to most casual observers, the moon will appear fully illuminated in the night sky from Sunday through Tuesday. In the Northern Hemisphere, the full moon that appears closest to the fall equinox is traditionally referred to as the "Harvest Moon."

3 0

2 years ago

Describe the basis concept of the atwood’s machine

Ann [662]

Answer:The Atwood Machine is a device that demonstrates the basic principles of acceleration and dynamics. You'll mostly see Atwood machines in Physics laboratories and classrooms. It consists of two objects with different masses that hang vertically from a frictionless pulley that has a very small, negligible mass.

Explanation:

8 0

3 years ago

a 3 kg piece of putty that is moving with a velocity of 10 m/s collides and sticks to an 8 kg bowling ball that was at rest. wha

defon

The final velocity is 2.7 m/s

Explanation:

We can solve this problem by using the principle of conservation of momentum: in fact, in absence of external forces, the total momentum of the system must be conserved before and after the collision.

Therefore we can write:

$p_i = p_f\\m_1 u_1 + m_2 u_2 = (m_1+m_2)v$