Answer:
a) During the reaction time, the car travels 21 m
b) After applying the brake, the car travels 48 m before coming to stop
Explanation:
The equation for the position of a straight movement with variable speed is as follows:
x = x0 + v0 t + 1/2 a t²
where
x: position at time t
v0: initial speed
a: acceleration
t: time
When the speed is constant (as before applying the brake), the equation would be:
x = x0 + v t
a)Before applying the brake, the car travels at constant speed. In 0.80 s the car will travel:
x = 0m + 26 m/s * 0.80 s = <u>21 m </u>
b) After applying the brake, the car has an acceleration of -7.0 m/s². Using the equation for velocity, we can calculate how much time it takes the car to stop (v = 0):
v = v0 + a* t
0 = 26 m/s + (-7.0 m/s²) * t
-26 m/s / - 7.0 m/s² = t
t = 3.7 s
With this time, we can calculate how far the car traveled during the deacceleration.
x = x0 +v0 t + 1/2 a t²
x = 0m + 26 m/s * 3.7 s - 1/2 * 7.0m/s² * (3.7 s)² = <u>48 m</u>
The correct answer is B. Calcite
Explanation:
Mohs hardness scale indicates the hardness of minerals using a scale from 1 to 10 as well as defining the objects or tools that can be used to scratch the minerals. These two features of minerals are shown in the table of the image. About this, it is shown gypsum and talc can be scratched by just a fingernail, considering minerals with a hardness of 2.5 or below can be scratched by a fingernail. In the case of calcite that has a hardness of 3, this cannot be scratched by a fingernail, but it can be scratched by a penny, which works for minerals with a hardness of 3.5 or below. Thus, the correct answer is Calcite.
By absorbing solar radiation and releasing heat needed to drive the atmospheric circulation
Answer:
You will be able to tell whether the unknown cell is from an animal or from a plant through the knowledge of difference between plants and animal cells.
Explanation:
A cell can be defined as the simplest bit of living matter which exhibits a variety of shapes and sizes and that can exist independently.
When a slide of an unknown cell is studied under a microscope, different cell structures would be observed which would be used to conclude if the cell on the slide is a plant or animal cell.
The following features are observed in a plant cell:
--> cellulose cell wall is present
--> Chloroplast is present
--> A large central vacuole is present
--> Centriole is absent
The following features are observed in animal cell:
--> Cellulose cell wall is absent
--> Chloroplast is absent
--> Small vacuoles is present
--> Centriole is present
The difference between a plant and an animal cell can be seen from the features above and a clear knowledge of this will help the student tell whether the unknown cell is from an animal or from a plant.
All vascular plants have parenchyma, collenchym<span>Vascular tissue transports food, water, hormones and minerals within the plant. Vascular tissue includes </span>xylem<span>, </span>phloem<span>, parenchyma, and cambium cells.</span>a, and sclerenchyma cells. Hoped it help!