Answer:
2.85 m
Explanation:
From trigonometry,
Cosine = Adjacent/Hypotenuse
Assuming, The wall, the ladder and the ladder forms a right angle triangle as shown in fig 1, in the diagram attached below.
cos∅ = a/H....................... Equation 1
Where ∅ = Angle the ladder makes with the horizontal, a = The horizontal distance from the bottom of the ladder to the wall, H = The length of the ladder.
make a the subject of the equation
a = cos∅(H)..................... Equation 1
Given: ∅ = 68 °, H = 7.6 m.
Substitute into equation 2
a = cos(68)×7.6
a = 0.375×7.6
a = 2.85 m.
Hence the horizontal distance from the bottom of the ladder to the wall = 2.85 m
The moon lacks an atmosphere compared to the Earth. Hope this helps!
Answer:
Sea-floor spreading occurs in the oceanic ridges. In there, volcanic activity, together with the gradual movement of the bottom, form new oceanic crust. This allows a better understanding of the continental drift explained by the theory of plate tectonics.
The greatest evidence for Sea-floor spreading is the oceanic trenches, the oceanic ridges, the magma protruding to the surface and the new seafloor.
In previous theories, continents were assumed to be transported across the sea. Harry Hess, in the 1960s, proposed the idea that the seabed itself moves as it expands from a central point. The theory is now accepted, and the phenomenon is thought to be caused by convection currents in the upper layer of the mantle.
C. in a covalent bond, they are shared by two atoms, while in an ionic bond, they are transferred
Refer to the diagram shown below.
d = distance (miles) from Alphaville to Betaville.
v = speed (mph) of the plane with no wind.
With no wind:
The time taken to travel a distance of 2d is 4 hrs, 48 min = 4.8 hrs.
Therefore
2d/v = 4.8
v = 2d/4.8 = 0.4167d mph (1)
With the wind:
The velocity from Alphaville to Betaville is (v + 100) mph.
The time of travel is
t₁ = d/(v+100) h
The velocity from Betaville to Alphaville is (v - 100) mph.
The time of travel is
t₂ = d/)v-100) h
Because the return trip takes 5 hours, therefore
t₁ + t₂ = 5

(2)
From (1), obtain
2(0.4167)d² = 5[(0.4167d)² - 10⁴]
0.8334d² = 0.8682d² - 5 x 10⁴
0.0348d² = 5 x 10⁴
d = 1198.7 mi
Answer: 1199 miles (nearest integer)