How many millimeters is represented by 6.7 cm

You place ammonium nitrate crystals in water and stirred. As you do so, the container becomes cold to the touch. This an example

ankoles [38]

The process of flask becoming cold is due to endothermic reaction.

Answer: Option B

<u>Explanation:</u>

So two kinds of heat transfer can be possible in any chemical reaction. If the sample is considered as system and the sample container is considered as the surrounding, then heat transfer can occur between them.

If the heat is transferred from the surrounding to the system , then it is an endothermic reaction. And in those cases, the sample holder will be becoming colder. This is because the heat from the surrounding that is the container will be utilized to complete the reaction.

While when there is transfer of heat from the system to surrounding , it will be exothermic reaction and the beaker will be getting hot in this process. So in the present case, the container is becoming cold because of occurrence of endothermic process.

8 0

3 years ago

. A ball is thrown downward at a speed of 20 m/s. Choosing

a_sh-v [17]

The final velocity is $v = 20 - gt$

The distance traveled by the ball at time t is $y = y_o + (-20)t - \frac{1}{2} gt^2$

The maximum distance traveled by the object is $0 = (20)^2 - 2g(y-y_0)$

The given parameters;

initial velocity of the ball, u = 20 m/s

acceleration due to gravity, g = 9.8 m/s²

The final velocity can be calculate as;

$v = 20 - gt$

The distance traveled by the ball at time t;

$y = y_o + (-20)t - \frac{1}{2} gt^2$

The maximum distance traveled by the object is calculated as;

$v^2 = u^2 - 2g(y - y_0)\\\\0 = (20)^2 - 2g(y-y_0)$

Learn more here: brainly.com/question/16878713

3 0

2 years ago

If eight water waves pass an ocean buoy each minute, and successive wave crests are 20 m apart, find the wave speed:____________

Llana [10]

Answer:

The wave speed is calculated below:

Explanation:

Given,

number of waves passed per minute = 8

time period = 1 minute = 60 s

distance between successive wave crests = 20 m

waves passing interval per second = $\frac{8}{60}$ $s^{-1}$

Now,

wave speed = 20 m × $\frac{8}{60}$ $s^{-1}$

= $\frac{8}3}$ m/s

= 2.67 m/s

Hence the wave speed is 2.67 m/s.

4 0

3 years ago

Falls resulting in hip fractures are a major cause of injury and even death to the elderly. Typically, the hip’s speed at impact

Westkost [7]

Answer:

-5.8868501529 m/s² or -5.8868501529g

0.118909090909 s

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

g = Acceleration due to gravity = 9.81 m/s²

$v^2-u^2=2as\\\Rightarrow a=\dfrac{v^2-u^2}{2s}\\\Rightarrow a=\dfrac{1.3^2-2^2}{2\times 0.02}\\\Rightarrow a=-5.8868501529\ m/s^2$

Dividing by g

$\dfrac{a}{g}=\dfrac{-57.75}{9.81}\\\Rightarrow a=-5.8868501529g$

The acceleration is -5.8868501529 m/s² or -5.8868501529g

$v=u+at\\\Rightarrow t=\dfrac{v-u}{a}\\\Rightarrow t=\dfrac{1.3-2}{-5.8868501529}\\\Rightarrow t=0.118909090909\ s$

The time taken is 0.118909090909 s

7 0

2 years ago

A tree moves at 30 km/s relative to the Sun. A squirrel jumps from a branch on

tresset_1 [31]

The reasoning is wrong if we look into Newton's Law of gravitation.

Newton's law of gravitation states that every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

The law is written as follows;

$F = \frac{Gm_1m_2}{r^2}$

$r = \sqrt{\frac{Gm_1m_2}{F} }$

The distance between the two particles, is a function of force and their masses not necessarily time of motion.

In the given problem only time of motion was considered which is wrong.

Thus, the reasoning is wrong if we look into Newton's Law of gravitation.

Learn more here: brainly.com/question/19680441

7 0

2 years ago