1. A fish swims 340 feet. Is this a distance or a<br> displacement?

You are sitting on a deck of your house surrounded by oak trees. You hear the sound of an acorn hitting the deck. You wonder if

Black_prince [1.1K]

Answer: 96N

Explanation:

To calculate the velocity of the impact On the persons head, we have

h = gt²/2

14 = 9.81t²/2

t² = 28/9.8

t² = 2.86

t = 1.69s

V = u + at

V = 0 + 9.81*1.69

V = 16.58m/s

a(average) = (v1² + v2²) /2Δy

a(average) = 16.58² + 0)/2 * 0.005

a(average) = 274.8964/0.01

a(average) = 27489.64m/s²

Using newton's second law of motion,

F(average) = m * a(average)

F(average) = 0.0035 * 27489.64

F(average) = 96.21N

Therefore the force needed by the acorn to do much damage starts from 96N

8 0

3 years ago

While standing on the edge of the grand canyon, you see a rattlesnake and scream. You hear the echo of the scream off canyon flo

bezimeni [28]

Answer:

1904 m

Explanation:

$\pink{\frak{Given}}\begin{cases} \textsf{ You scream after seeing a rattle snake .}\\\textsf{Scream is heard after 11.2 s .} \end{cases}$

Here we need to find out the depth of the canyon . When you will scream after seeing a snake , the sound produced will travel till the end of the canyon and after hitting the end , it will travel back to you .

So if the depth of the canyon is d (say) , then the total distance travelled by the sound wave will be d + d = 2d .

And we know that the speed of the sound is approximately 340m/s in air , so we can use the formula distance = speed * time to calculate the depth of the canyon . So ,

$\sf \longrightarrow Distance = (Speed)(Time) \\$

$\sf \longrightarrow 2d = 340m/s * 11.2 s\\$

$\sf \longrightarrow d = \dfrac{340m/s * 11.2s}{2} \\$

$\sf \longrightarrow \boxed{\bf Depth_{canyon}= 1904m }\\$

6 0

2 years ago

1. A particular lever is 90.0% efficient. If 50.0 J of work are done on the lever, then how much work does the lever do on its l

laila [671]

Answer:

Explanation:

Using the efficiency formula;

Efficiency = Work done by the machine (output)/work done on the machine (input) ×100%

Efficiency =w/50 ×100

90 = 100w/50

Cross multiply

90×50 = 100W

4500 = 100W

W = 4500/100

W = 45Joules

Hence the lever does 45Joules of work on its load

2) Mechanical Advantage= Load/Effort

Given

MA = 4

Load = 500N

4 = 500/Effort

Effort = 500/4

Effort =125N

Hence the effort required to lift the load is 125N

8 0

3 years ago

A diver named Jacques observes a bubble of air rising from the bottom of a lake (where the absolute pressure is 3.50 atm) to the

Studentka2010 [4]

Answer:

A) the ratio of volumes of the bubble is Vs/Vb= 3.74

B) would not be safe since Vs/Vb== 3.5 and there is no lung capacity to store such amount of volume, and thus would generate an unsafe pressure over the lungs. would be better to release air accordingly to maintain safe conditions.

Explanation:

assuming the gas of the bubble behaves as ideal gas

P * V = n * R * T

where P= absolute pressure, V= volume occupied by the gas, n = number of moles , R = ideal gas constant , T = absolute temperature

if we assume that the mass of the bubble remains constant ( that is, it does not capture other bubbles during ascension of disaggregate into smaller ones and there is no mass transfer into the bubble due to diffusion)

inicial state) Pb * Vb = n * R * Tb

final state) Ps * Vs = n * R * Ts

dividing both equations

(Ps/Pb)(Vs/Vb) = Ts/Tb

therefore

Vs/Vb= (Ts/Tb) (Pb/Ps)

since Tb = 4°C = 277 K and Ts= 23°C = 296 K

Vs/Vb= (Ts/Tb) (Pb/Ps) = (296K/277K)*(3.5 atm/1 atm) = 3.74

B) if the T remains constant Ts=Tb and thus

Vs/Vb= (Ts/Tb) (Pb/Ps)= 1* (Pb/Ps) = 3.5 atm/1 atm = 3.5

it would not be safe since there is no lung capacity to store such amount of volume, and thus would generate an unsafe pressure over the lungs. would be better to release air accordingly to maintain safe conditions.

8 0

3 years ago

When stated as a percentage, the useful energy transferred by a device divided by the total energy supplied to the device is kno

Verdich [7]

Efficiency

Explanation:

Efficiency is a ratio/percentage that is useful in comparing the energy transferred by a device to the total energy supplied to it.

Percentage efficiency = $\frac{energy input}{total energy supplied}$ x 100

As with most system, none is 100% efficient.
During energy is transferred some are lost and only a little portion is used in doing actual work by the machine.
This validates the third law of thermodynamics which proposes that no system is 100% efficient.
A 100% efficiency implies total energy input is used doing all the work.
This is impossible. The bulk of the energy goes into heating the system.

learn more:

Third law of thermodynamics brainly.com/question/3564634

#learnwithBrainly

4 0

3 years ago

1. A fish swims 340 feet. Is this a distance or a displacement?