1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
avanturin [10]
3 years ago
15

A 2-kilogram object falls 3 meters. a. How much potential energy did the object have before it fell? b. How much work was accomp

lished by the fall
Physics
1 answer:
stiks02 [169]3 years ago
6 0
Below are the answers:

(a) Ep = mass x gravitational acceleration x height 
<span>= 2kg x 9.8ms-2 x 3m </span>
<span>= 58.8J </span>

<span>(b) F = mg </span>
<span>= 2kg x 9.8ms-2 </span>
<span>= 19.6N </span>
<span>W = Fd </span>
<span>= 19.6N x 3m </span>
<span>= 58.8J 
</span>
Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.
You might be interested in
Please help meh its due
Fed [463]
-0.000393025 light years
3 0
2 years ago
Read 2 more answers
What is work please give ans​
Fed [463]
Work= force x displacement :)
8 0
2 years ago
A world-class sprinter running a 100 m dash was clocked at 5.4 m/s 1.0 s after starting running and at 9.8 m/s 1.5 s later. In w
cupoosta [38]

Answer:

<em>The output power is greater in the interval from 1.0 s to 2.5 s</em>

Explanation:

<u>Physical Power </u>

It measures the amount of work W an object does in certain time t. The formula needed to compute power is

\displaystyle P=\frac{W}{t}

Work can be computed in several ways since we are given the motion conditions, we'll use this formula, for F= applied force, x=distance parallel to F

W=F.x

The second Newton's law gives us the net force as

F=m.a

being m the mass of the object and a the acceleration it has for a given period of time. In our problem, we have two different behaviors for each interval and we must calculate this force since the acceleration is changing. Let's calculate the acceleration in the first interval. We can use the formula for the final speed vf knowing the initial speed vo (which is 0 because the sprinter starts from rest), the acceleration a, and the time t:

v_f=v_o+at

v_f=at

Solving for a

\displaystyle a=\frac{v_f}{t}={5.4}{1}

a=5.4\ m/s^2

The distance traveled in the interval is given by

\displaystyle x=v_o.t+\frac{a.t^2}{2}

Since vo=0

\displaystyle x=\frac{a.t^2}{2}=\frac{5.4(1)^2}{2}

x=2.7\ m

The force is given by

F=m.a

We don't know the value of m, so the force is

F=2.7m

Computing the work done by the sprinter

W=F.x=2.7m(5.4)

W=14.58m

The power is finally computed

\displaystyle P=\frac{W}{t}=\frac{14.58m}{1}

P=14.58m

During the second interval, from t=1 sec to 1.5 sec, the speed changes from 5.4 m/s to 9.8 m/s. This allows us to compute the second acceleration

\displaystyle a=\frac{v_f-v_o}{t}=\frac{9.8-5.4}{0.5}

a=8.8\ m/s^2

The distance is

\displaystyle x=(5.4).(0.5)+\frac{8.8(0.5)^2}{2}

x=3.8\ m

The net force is

F=m(8.8)=8.8m

The work done by the sprinter is now computed as

W=8.8m(3.8)=33.44m

At last, the output power is

\displaystyle P=\frac{33.44m}{0.5}=66.88m

By comparing both results, and being m the same for both parts, we conclude the output power is greater in the interval from 1.0 s to 2.5 s

6 0
3 years ago
Consider a skateboarder who starts from rest at the top of ramp that is inclined at an angle of 18.0 ∘ to the horizontal.
kotegsom [21]

Answer:

Explanation:

v= u + at

v is final velocity , u is initial velocity . a is acceleration and t is time

Initial velocity u = 0 . Putting the given values in the equation

v = 0 + g sin 18 x 3.5

= 10.6 m /s

3 0
3 years ago
A rock is thrown horizontally from a high building at 33.8 m/s. What is the magnitude of its velocity 4.25 s later?
Alex17521 [72]
<h2>Answer:53.63ms^{-2}</h2>

Explanation:

The equations of motion used in this question is v=u+at

When a object is projected horizontally from a sufficiently height,the x-component of acceleration remains zero because there is no force that drags the object in x direction.

But,due to gravity,the object accelerates downward at a rate of 9.8ms^{-2}.

In X-Direction,

Given that initial velocity=u_{x}=33.8ms^{-1}

Using v=u+at,

v_{x}=33.8+(0)4.25=33.8ms^{-1}

In Y-Direction,

Given that initial velocity=u_{x}=0ms^{-1}

Using v=u+at,

v_{y}=0+(9.8)4.25=41.65ms^{-1}

v=\sqrt{v_{x}^{2}+v_{y}^{2}}

v=\sqrt{1142.44+1734.72}=\sqrt{2877.163}=53.63ms^{-1}

7 0
3 years ago
Other questions:
  • Using evidence from the article, defend the concept that
    6·2 answers
  • A metal ball attached to a spring moves in simple harmonic motion. The amplitude of the ball's motion is 11.0 cm, and the spring
    14·1 answer
  • Which factors affect the speed of ocean waves?
    9·2 answers
  • A ray diagram is shown
    8·2 answers
  • What is the formula for Wedge
    6·1 answer
  • A woman takes her dog Rover for a walk on a leash. She pulls on the leash with a force of 30.0 N at an angle of 29° above the ho
    9·1 answer
  • What direction does tangential velocity point?
    7·1 answer
  • The Grand Canyon is more than 400 km long and in some places almost 2 km deep. Which model best represents the main process that
    13·1 answer
  • A standard for comparison is called a frame of reference<br>True or False​​
    10·2 answers
  • A 500-W heating coil designed to operate from 110V is made of Nichrome wire 0.500 mm in diameter. (b) What If? Now consider the
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!