Answer:
The tip of her shadow is moving at the speed of 9.66 ft/sec
Explanation:
The height of the street light = 19 feet
The height of the woman = 5.25 feet
Distance between the woman and the base of the pole, x = 35 ft
The speed of the woman towards the pole, dx/dt = 7ft/sec
The distance from the base of the streetlight to the tip of the woman's shadow = y
The distance from the woman to the tip of her shadow = y - x
The diagram illustrating this description is shown below
Using similar triangle:

Find the derivative of both sides with respect to time, t

The tip of her shadow is moving at the speed of 9.66 ft/sec
Answer:
Increasing speed.
Explanation:
In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.
This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.
Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.
Mathematically, acceleration is given by the equation;

In this scenario, an object moves with a positive acceleration. Thus, the object is moving with an increasing speed and as such it has acceleration in the same direction as its velocity with respect to time.
Answer:
32.9166667 m / s^2
Explanation:
s = 4.25km (1000m / 1km)
= 4250m
u = 20m/s
delta T = 20min (60sec / 1min)
= 1200s
Use formula s = ut + (1/2)at^2
4250m = 20m/s * 1200s + (1/2)a*1200s^2
Rearrange it to find a
a = (s-ut) / (1/2 * t^2)
a = (4250m - 20m/s*1200s) / (1/2 * 1200s^2)
a = -32.9166667 m / s^2
Answer:
Mechanical weathering is the physical breakdown of rock into smaller pieces. Chemical weathering is the breakdown of rock by chemical processes.
Explanation:
Mechanical weathering (also called physical weathering) breaks rock into smaller pieces. These smaller pieces are just like the bigger rock, just smaller. That means the rock has changed physically without changing its composition. The smaller pieces have the same minerals, in just the same proportions as the original rock.
Chemical weathering is the other important type of weathering. Chemical weathering is different from mechanical weathering because the rock changes, not just in size of pieces, but in composition Chemical weathering works through chemical reactions that cause changes in the minerals.