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
Andreas93 [3]
4 years ago
14

An object is thrown straight up with an initial velocity of 10 m/s, and there is an air resistance force causing an acceleration

of 3 m/s2 opposite the direction of motion. With what speed does the object return to the ground?
Physics
1 answer:
lana [24]4 years ago
8 0

Answer:

Vf= 7.29 m/s

Explanation:

Two force act on the object:

1) Gravity

2) Air resistance

Upward motion:

Initial velocity = Vi= 10 m/s

Final velocity = Vf= 0 m/s

Gravity acting downward =  g = -9.8 m/s²

Air resistance acting downward = a₁ = - 3 m/s²

Net acceleration = a = -(g + a₁ ) = - ( 9.8 + 3 ) = - 12.8 m/s²

( Acceleration is consider negative if it is in opposite direction of velocity )

Now

2as = Vf² - Vi²

⇒ 2 * (-12.8) *s = 0 - 10²

⇒-25.6 *s = -100

⇒ s = 100/ 25.6

⇒ s = 3.9 m

Downward motion:

Vi= 0 m/s

s = 3.9 m

Gravity acting downward =  g = 9.8 m/s²

Air resistance acting upward = a₁ = - 3 m/s²

Net acceleration = a = g - a₁  =  9.8 - 3  = 6.8 m/s²

Now

2as = Vf² - Vi²

⇒ 2 * 6.8 * 3.9 = Vf² - 0

⇒ Vf² = 53. 125

⇒ Vf= 7.29 m/s

You might be interested in
What is the specific enthalpy of benzene vapor at 45 c and 0.7 atm absolute pressure, relative to a reference state of benzene v
vazorg [7]

The specific enthalpy of benzene vapor at 45 c and 0.7 atm absolute pressure, relative to a reference state of benzene vapor at 45 c and 1.27 atm absolute pressure will be 0 kJ/mol.

<h3>What is specific enthalpy and how was it calculated in the question?</h3>

A thermodynamic system has a property called enthalpy (H). It is calculated by the sum of the internal energy (U) of the thermodynamic system and the product of its volume (V) and pressure (p). The SI Unit is Joule (J).

Equation:

H = U+pV

The specific enthalpy of vapor can be defined as the amount of energy spent in order to transform a liquid substance into its vapor or gaseous form. The SI Unit is kJ/mol.

In the above question, the formula to be used is

P1/P2 = (Δ Hvap)/R)(1/T2-1/T1)

T1 & P1 --> the starting temperature & pressure respectively (= 1.27 atm and 45c),

T2 & P2 --> the final temperature & pressure respectively (= 0.7 atm and 45c),

R --> the real gas constant i.e. 8.314kJ/mol and

ΔHvap --> The specific enthalpy of vaporization.

Putting the values in the equation;

1.27/0.7=(ΔHvap/8.314)(1/45-1/45)

Hence as after subtracting the equation becomes 0, our final answer also comes out to be ΔHvap= 0 kJ/mol.

To know more about specific enthalpy, visit:

brainly.com/question/16244647  

#SPJ4

6 0
2 years ago
3. How does Earth’s rotation affect our view of stars
Elis [28]
Since we ride along with the Earth while it's doing whatever it does,
the Earth's rotation causes our eyes to constantly point in a different
direction.

If we try to keep watching one star, we have to keep changing the
direction of our eyes to keep looking at the same star. 

We can't feel the Earth rotating, so our brains say that the star  ... and
the sun and the moon too ... is actually moving across the sky.
5 0
3 years ago
Read 2 more answers
True or false your vocal cords act like a guitar string when it comes to sound
torisob [31]

Answer:

True

Explanation:

8 0
3 years ago
Read 2 more answers
A 64.8 kg astronaut is on a space walk when the tether line to the shuttle breaks. The astronaut is able to throw a 11.0 kg oxyg
Umnica [9.8K]

dfdfdfdddfdddddddddddddddd

6 0
3 years ago
The chicken's eggs are fertilized interally or externally
zlopas [31]
The chicken's eggs are fertilized interally
6 0
3 years ago
Other questions:
  • For a human zygote to become an embryo it must undergo
    15·2 answers
  • A pendulum has a 0.35\ \text{kg}0.35 kg0, point, 35, space, start text, k, g, end text mass oscillating at a small angle from a
    8·1 answer
  • Ccording to coulomb's law, which pair of charged particles has the lowest potential energy? according to coulomb's law, which pa
    11·2 answers
  • Planets in our solar system do not revolve around the sun in perfect circles. Their orbits are more like ovals that scientists d
    11·2 answers
  • A net force of 500 newtons causes
    14·1 answer
  • You want to create an electric field vector E = &lt; 0, 5 104, 0&gt; N/C at location &lt; 0, 0, 0&gt;. Where would you place a p
    14·1 answer
  • What compound is formed when two hydrogen atoms and one oxygen atom joined together?
    9·2 answers
  • Help please am stuck
    9·1 answer
  • Be sure to answer all parts. Assume the diameter of a neutral helium atom is 1.40 × 102 pm. Suppose that we could line up helium
    9·1 answer
  • ou are pushing a 20-kg box along a horizontal floor. Friction acts on the box. When you apply a horizontal force of magnitude 48
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!