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3 years ago

Answer correctly this 14 questions, please and earn 15pts and the brainlist answer!

Physics

2 answers:

sammy [17]3 years ago

5 0

1. K 2. P 3. K 4. K 5. P 6. K 7. K 8. P 9. K 10. P

11. A golf ball flying through the air. 12. A skateboard rolling down a hill.
13. A roller coaster car sitting at the top of a drop.
14. Leaning up against a wall.

nikitadnepr [17]3 years ago

3 0

K, P, K, K, P, K, K, P, K, P.
Kinetic:
Walking down the hall.
Dropping a pencil.
Potential:
A book sitting on the edge of a shelf.
A stretched out rubber band.

You might be interested in

Adam drops a ball from rest from the top floor of a building at the same time Bob throws a ball horizontally from the same locat

guapka [62]

Answer:

Both balls hit the ground at the same time

Explanation:

Adam drops the ball from rest, so the ball just "<em>falls</em>" in vertical direction, being gravity its only acceleration, for cinematic movements we use that:

$y(t)=y_{0}+v_{0y}t+\frac{1}{2}gt^{2}$

In this case we have that gravity is negative, and as Adam drops the ball, $v_{0y}=0$

Bob throws the ball horizontally, so the movement will be a <em>parabola</em>, we can divide into horizontal direction, and vertical direction.

But we only need to analize the vertical movement, in wich again the only acceleration is gravity, and compare it with Adam's ball. Again we have that gravity is negative, and as the initial throw is horizontal, $v_{0y}=0$

Finally, we have that

$y(t)=h-\frac{1}{2}gt^{2}$

where

$h=y_{0}$

both for Adam's vertical drop, and for Bob's vertical component of the parabolic throw.

Now, if we put $y(t)=0$ (the origin of the vertical coordinate), we get for both cases that

$h=\frac{1}{2}gt^{2}$

where we can clear the value for the time t, of the fall, wich will be the same in both cases.

Hence, both balls hit the ground at the same time.

3 0

3 years ago

In a type of chemical reaction called thermal decomposition, heat is added to a substance, which then splits apart to form sever

exis [7]

The answer is a. endothermic.
In endothermic reaction, as the name suggests, the reactants require energy absorption to form and complete the chemical reaction to form products.
And even if you don't know the answer, you can exclude all other answers by scientific logic and you will be left with the correct answer.

Hope this helps.

5 0

3 years ago

Find the height or length of these natural wonders in km, m, and cm.A. A cave system with a mapped length of 354 miles.B. A wate

cricket20 [7]

Explanation:

Some standard unit conversion are 1 mile = 1.609344 km, 1 ft.= 30.48 cm,

1 km= 1000 m or 1 m = 0.001 km and 1 m= 100 cm or 1 cm=0.01 m.

Now, use these values to convert the given lengths.

A. length of cave = 5 miles (given)

From standard value 1 mile = 1.609344 km

$\Rightarrow$ 5 miles = $\times$ 1.609344 km= 8.04672 km,

$\Rightarrow$ 5 miles =8.04672 $\times$ 1000 m= 8046.72 m [ as 1 km = 1000 m]

$\Rightarrow$ 5 miles = 8046.72 $\times$ 100 cm=804672 cm

B. Height of the waterfall = 1235 ft. (given)

1 ft.= 30.48 cm [ from standard value]

$\Rightarrow$ 1235.2 ft.= 1235.2 $\times$ 30.48 cm=37648.896 cm,

$\Rightarrow$ 1235.2 ft.=37648.896 $\times$ 0.01 m =376.48896 m [ as 1 cm = 0.01 m]

$\Rightarrow$ 1235.2 ft.=376.48896 $\times$ 0.001 km =0.37648896 km [ as 1 m = 0.001 km]

C. Height of the mountain= 21320 ft. (given)

From standard value: 1 ft.= 30.48 cm

$\Rightarrow$ 21320 ft.= 21320 $\times$ 30.48 cm=649833.6 cm,

$\Rightarrow$ 21320 ft.=649833.6 $\times$ 0.01 m =6498.336 m [ as 1 cm = 0.01 m]

$\Rightarrow$ 21320 ft.=6498.336 $\times$ 0.001 km =6.498336 km [ as 1 m = 0.001 km].

D. Depth of canyon =6630 ft.

From standard value: 1 ft.= 30.48 cm

$\Rightarrow$ 6630 ft.= 6630 $\times$ 30.48 cm=202082.4 cm,

$\Rightarrow$ 6630 ft.=202082.4 $\times$ 0.01 m =2020.824 m [ as 1 cm = 0.01 m]

$\Rightarrow$ 6630 ft.=2020.824 $\times$ 0.001 km =2.020824 km [ as 1 m = 0.001 km].

4 0

4 years ago

Who is the greek philisopher who came up with the idea that atoms exist

Mariulka [41]

Greek philosophers Leucippus and Democritus first developed the concept of the atom in the 5th century B.C.E.

4 0

3 years ago

Suppose the price of electricity is 12.75 cents per kWºh. What

adell [148]

Answer:

The difference between the cost of operating LED and incandescent bulb is $5.1

Explanation:

We are given the cost of electricity that is 12.75 cents per kWh. We want to find out the difference in the operating cost of an incandescent and LED bulb for a time period of 2,000 hours.

Since we are not given the rating of the incandescent bulb and LED bulb, we will assume their ratings.

For a light intensity of 250 Lumens;

The average rating of an LED bulb is approximately 5 Watts.

The average rating of an incandescent bulb is approximately 25 Watts.

Now lets find out the kWh of each bulb.

Energy = Power×Time

For LED bulb:

E = 5×2,000 = 10,000 Wh

Divide by 1000 to convert into kWh

E = 10,000/1000 = 10 kWh

Cost = 12.75×10 = 127.5 cents

Cost = $1.27

For Incandescent bulb:

E = 25×2,000 = 50,000 Wh

Divide by 1000 to convert into kWh

E = 50,000/1000 = 50 kWh

Cost = 12.75×50 = 637.5 cents

Cost = $6.37

Difference in Cost:

Difference = $6.37 - $1.27 = $5.1

Therefore, the difference between the cost of operating LED and incandescent bulb is $5.1.

5 0

3 years ago