In reaching her destination, a backpacker walks with an average velocity of 1.19 m/s, due west. This average velocity results because she hikes for 5.96 km with an average velocity of 3.10 m/s, due west, turns around, and hikes with an average velocity of 0.744 m/s, due east. How far east did she walk

 x₂ = 4.455 m

Explanation:

The average speed is defined as the displacement traveled between the time interval

         v_average =  

in this case we have a first stop walking west at speed v = 3.10 m / s a ​​distance of x = 5.96 km = 5.96 10³ m

Let's find the time it takes on this tour

          v = x / t

          t = x / v

          t₁ = 5.96 10³ / 3.10

          t₁ = 1.9226 10³ s

in a second to walk east at a speed of v₂ = 0.744 m / s

           v₂ = x₂ / t₂

           t₂ = x₂ / v₂

for full movement

let's assume that the eastward movement is positive

         v =

         v =

the only unknown term is the distance to the east. We replace and resolve

         1.19 =

         1.19 (1.92 10³ + ) = x₂ 1.92 10³ - 5.96 10³

          2.2848 10³ + 1.599 x₂ = 1.92 10³ x₂ - 5.96 10³

          x₂ (1.92 10³ - 1.599) = 2.2848 10³ + 5.96 10³

          x₂ = 8.5448 10³ / 1.918 10³

          x₂ = 4.455 m

d

explanation:

v=uf/(u-f)

= 5.10/(5-10) convex lens has positive focal length

=50/-5

=-10 cm (formed at other side)

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.