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4 years ago

How much work is done in holding a 15 N sack of potatoes while waiting in line at the

Physics

1 answer:

marta [7]4 years ago

4 0

Answer: 2700 Joules

Explanation:

Given variables are:

Workdone (w) = ?

Weight of sack (w) = 15N

Time taken (t) = 3 minutes

The standard unit of time is seconds, so convert 3 minutes to seconds

(If 1 minute = 60 seconds

3 minutes = 3 x 60 = 180 seconds)

Recall that work is done is when force is applied on an object over a distance

i.e Workdone = force x distance.

(However, the force acting on the sack of potatoes is weight)

Hence, workdone = weight x time

w = 15N x 180 seconds

w = 2700 J

thus, 2700 joules of work was done.

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You are heating an iron to iron the shirt you're going to wear to school tomorrow. Which of the following best describes the tra

telo118 [61]

Answer:

electrical to the thermal

Explanation:

6 0

3 years ago

jet is flying at 500 mph east relative to the ground. A Cessna is flying at 150 mph 60° north of west relative to the ground. Wh

Greeley [361]

Answer:

C. 590 mph

$\vert v_{cj}\vert=589.49\ mph$

Explanation:

Given:

velocity of jet, $v_j=500\ mph$
direction of velocity of jet, east relative to the ground
velocity of Cessna, $v_c=150\ mph$
direction of velocity of Cessna, 60° north of west

Taking the x-axis alignment towards east and hence we have the velocity vector of the jet as reference.

Refer the attached schematic.

So,

$\vec v_j=500\ \hat i\ mph$

$\vec v_c=150\times (\cos120\ \hat i+\sin120\ \hat j)$

$\vec v_c=-75\ \hat i+75\sqrt{3}\ \hat j\ mph$

Now the vector of relative velocity of Cessna with respect to jet:

$\vec v_{cj}=\vec v_j-\vec v_c$

$\vec v_{cj}=500\ \hat i-(-75\ \hat i+75\sqrt{3}\ \hat j )$

$\vec v_{cj}=575\ \hat i-75\sqrt{3}\ \hat j\ mph$

Now the magnitude of this velocity:

$\vert v_{cj}\vert=\sqrt{(575)^2+(75\sqrt{3} )^2}$

$\vert v_{cj}\vert=589.49\ mph$ is the relative velocity of Cessna with respect to the jet.

8 0

3 years ago

Which force prevents protons from repelling each other inside a nucleus?

Stella [2.4K]

Answer:

So, the correct answer is the strong nuclear force. It actually pulls together nuetrons and protons that are in the nucleus. At very tiny distances only, like those inside the nucleus, so, this strong force succeded in dealing with the electromagnetic force, and it basically stops the electrical repulsion of protons from blowing apart the nucleus.

Mark as brainlies please, I need a few more :D

4 0

3 years ago

A bat emitts a sonar sound wave (343 m/s) that bounces off a mosquito 8.42 m away

Varvara68 [4.7K]

The time lapse between when the bat emits the sound and when it hears the echo is 0.05 s.

From the question given above, the following data were obtained:

Velocity of sound (v) = 343 m/s

Distance (x) = 8.42 m

Time (t) =?

We can obtain obtained the time as illustrated below:

v = 2x / t

343 = 2 × 8.42 / t

343 = 16.84 / t

Cross multiply

343 × t = 16.84

Divide both side by 343

t = 16.84/343

t = 0.05 s

Thus, the time between when the bat emits the sound and when it hears the echo is 0.05 s.

<h3>How does a bat know how far away something is?</h3>

A bat emits a sound wave and carefully listens to the echoes that return to it. The returning information is processed by the bat's brain in the same way that we processed our shouting sound with a stopwatch and calculator. The bat's brain determines the distance of an object by measuring how long it takes for a noise to return.

Learn more about time elapses between when the bat emits the sound :

brainly.com/question/16931690

#SPJ4

Correction question:

A bat emits a sonar sound wave (343 m/s) that bounces off a mosquito 8.42 m away. How much time elapses between when the bat emits the sound and when it hears the echo? (Unit = s)

8 0

2 years ago

Inga [223]

Answer is c, they are equal:

Explanation:

4 0

3 years ago