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
Marianna [84]
3 years ago
9

A sled is moving down a steep hill. The mass of the sled is 50 kg and the net force acting on it is 20 N. What must be done to f

ind the acceleration of the sled?
Physics
1 answer:
amid [387]3 years ago
6 0

You need to first measure the angle of descent, i.e. the angle the hill makes with the ground. Then identify the forces acting on the sled, split them up into horizontal and vertical components, or into components that are parallel and perpendicular to the hill, and use Newton's second law to determine the components of the sled's acceleration vector.

There are at least 2 forces acting on the sled:

• its weight, pointing downward with magnitude <em>W</em> = <em>m g</em>

• the normal force, pointing perpendicular to the hill and away from the ground with mag. <em>N</em>

The question doesn't specify, but there might also be friction to consider, indicated in the attachment by the vector <em>F</em> pointing parallel to the slope of the hill and opposing the direction of the sled's motion with mag. <em>F</em>.

Splitting up the forces into parallel/perpendicular components is less work. By Newton's second law, the net force (denoted with ∑ or "sigma" here) in a particular direction is equal to the mass of the sled times its acceleration in that direction:

∑ (//) = <em>W</em> (//) = <em>m</em> <em>a</em> (//)

∑ (⟂) = <em>W</em> (⟂) + <em>N</em> = <em>m </em><em>a</em> (⟂)

where, for instance, <em>W</em> (//) denotes the component of the sled's weight in the direction parallel to the hill, while <em>a</em> (⟂) denotes the component of the sled's acceleration perpendicular to the hill. If there is friction, you need to add -<em>F</em> to the first equation.

If the hill makes an angle of <em>θ</em> with flat ground, then <em>W</em> makes the same angle with the hill so that

<em>W</em> (//) = -<em>m g </em>sin(<em>θ</em>)

<em>W</em> (⟂) = -<em>m g</em> cos(<em>θ</em>)

So we have

<em>-m g </em>sin(<em>θ</em>) = <em>m</em> <em>a</em> (//)   →   <em>a</em> (//) = -<em>g </em>sin(<em>θ</em>)

<em>-m g</em> cos(<em>θ</em>) + <em>N</em> = <em>m </em><em>a</em> (⟂)   →   <em>a</em> (⟂) = 0

where the last equality follows from the fact that the normal force exactly opposes the perpendicular component of the weight. This is because the sled is moving along the slope of the hill, and not into the air or into the ground.

Then the acceleration vector is

<em>a</em> = <em>a</em> (//)

with magnitude

||<em>a</em>|| = <em>a</em> = <em>g </em>sin(<em>θ</em>).

You might be interested in
If you run at 12 m/s fr 15 minutes, how far will you go
notsponge [240]

Answer:

180m

Explanation:

We can use the formula [ d = st ].

12 * 15 = 180m

Best of Luck!

4 0
3 years ago
Please can someone give a clear explanantion, <br><br> no extra links thanks
Tems11 [23]

Answer:

the extension recorded by the student would be smaller than the actual extension of the spring

3 0
3 years ago
What shape is the Milky way galaxy
gizmo_the_mogwai [7]
It appears to be a <span>spiral shape. </span>
5 0
3 years ago
Read 2 more answers
Why did the following change occur? the snow that covered the ground all winter began to melt, temperatures rose, and flowers st
FromTheMoon [43]

Answer:C

Explanation:

8 0
3 years ago
Read 2 more answers
How do I answer this question
maria [59]

Answer:

what question

Explanation:

6 0
3 years ago
Read 2 more answers
Other questions:
  • Suppose you were far from a planet that had a very strong gravitational field, and an emission line spectrum source on the surfa
    12·1 answer
  • Which of the following best describes a property of water?
    12·2 answers
  • The charge on the square plates of a parallel-plate capacitor is Q. The potential across the plates is maintained with constant
    12·1 answer
  • Helloooooooooooo<br><br><br> A) HI<br><br> B) GO AWAY<br><br> C) BYE FELICIA<br><br> D) HELLO MATE
    13·1 answer
  • An unbalanced force of 500 N is applied to a 75 kg object. What is the acceleration of the object?
    14·2 answers
  • It is recommended that adults should get at least 150 minutes of moderate-intensity physical activity each week. they should als
    15·1 answer
  • A 2 kg ball of clay moving at 35 m/s strikes a 10 kg box initially at rest. What is the velocity of the box after the collision?
    9·1 answer
  • 4) Based on your results, what can you infer about the distribution of
    15·1 answer
  • Where do you weight more on top of Mt. Everest (Highest Mt. in the world) or at the beach
    12·1 answer
  • A 200 N object is resting on a surface with a coefficient of static friction equal to 0.15. A person pushes horizontally with a
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!