All categories

3 years ago

14) the formula k2s indicates that

1 answer:

Ivan3 years ago

6 0

14.) c) there are two potassium ions for each ion of sulfur. 15.) b) Lithium fluoride. 16.) d) carbon-12 atom. 17.) <span>c) nonmetal fluorine.</span>

You might be interested in

How many seconds have you been alive? If your 16

kolbaska11 [484]

504921600 seconds. Hope this helps!

3 0

3 years ago

The formula d = rt gives the distance d traveled in time t at rate r. A train travels 163.2 miles in 2.4 hours, traveling at a c

Alex17521 [72]

Since d= 163.2 and t = 2.4, we divide 163.2 by 2.4 to get 68 miles per hour.

6 0

3 years ago

Please Help!!! An engine takes 3,000 J from a hot reservoir and expels 2,400 J to a cold reservoir. What is the thermal efficien

Murljashka [212]

Answer:

80%

Explanation:

Thermal efficiency is a measure of the extent to which a heat engine is able to convert to other form. It is measure in percentage.

Thermal efficiency = $\frac{E_{out} }{E_{in} }$ × 100%

Where $E_{in}$ is the input energy and $E_{out}$ is the output energy.

Given that: $E_{in}$ = 2400 J and $E_{out}$ = 3000 J, therefore:

Thermal efficiency = $\frac{2400}{3000}$ × 100%

= 80%

The thermal efficiency of the engine is 80%.

4 0

4 years ago

Question 3 A woman sitting in a stationary car notices a man cycling past her at 40 km/hr. Five seconds after he passes her car,

Naya [18.7K]

The shortest possible distance in which she catches up with the man is 129.7 m.

The given parameters:

speed of the man, v₁ = 40 km/hr

speed of the woman, v₂ = 70 km/hr

time when the woman started moving, t₁ = 5 seconds

To find:

the shortest distance when she catches up with the man

Convert the given speed in km/h to m/s

3.6 km/h = 1 m/s
40 km/h = 40/3.6 = 11.11 m/s
70 km/h = 70/3.6 = 19.44 m/s

Calculate the distance moved by the man before she started following him.

Distance moved by the man = speed x time

= 11.11 m/s x 5 s

= 55.55 m

Let the time the woman catches up with the man = t

Apply the following simple principle to calculate the time.

The man is moving forward and the woman is moving forward to close the gap between them, thus both speeds are working against each other.

$(v_2-v_1)t = 55.55 \ m$

the difference in the speed is because they are working against each other.

$(19.44 - 11.11)t = 55.55\\\\8.33t = 55.55\\\\t = \frac{55.55}{8.33} \\\\t = 6.67 \ s$

The time when the woman catches up with the man = 6.67 s

The shortest distance at which the woman catches up with the man is calculated as;

Shortest distance = woman's speed x time when she catches up

= 19.44 m/s x 6.67 s

= 129.7 m

Thus, the shortest possible distance in which she catches up with the man is 129.7 m.

Learn more here: https://brainly.in/question/9541933?tbs_match=3

5 0

3 years ago

A force of 400-N pushes on a 25-kg box horizontally. The box accelerates at 9 m/s? Find the coefficient of kinetic friction betw

umka2103 [35]

Answer:

Explanation:

Using the Newtons law of motion;

$\sum Fx = ma_x\\Fm - Ff = ma_x$

Fm is the moving force = 400N

Ff is the frictional force = μR

μ is the coefficient of kinetic friction

R is the reaction = mg

m is the mass

a is the acceleration

The equation becomes;

$Fm - \mu R = ma_x\\Fm - \mu mg = ma_x\\400- \mu (25)(9.8) = 25(9)\\400 - 254.8 \mu = 225\\- 254.8 \mu = 225 - 400\\- 254.8 \mu = -175\\ \mu = \frac{-175}{- 254.8} \\\mu = 0.69$

Hence the coefficient of kinetic friction between the box and floor is 0.69

7 0

3 years ago