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
Nonamiya [84]
3 years ago
14

A block of mass 2.00 kg is initially at rest at x=0 on a slippery horizontal surface for which there is no friction. Starting at

time t=0, a horizontal force Fx(t)=β−αt is applied to the block, where α = 6.00 N/s and β = 4.00 N.
What is the largest positive value of x reached by the block?
How long does it take the block to reach this point, starting from t = 0?
What is the magnitude of the force when the block is at this value of x?
Physics
1 answer:
Allisa [31]3 years ago
8 0

Answer:

   x = 1,185 m ,     t = 4/3 s ,  F = - 4 N

Explanation:

For this exercise we use Newton's second law

         F = m a = m dv /dt

        β - α t = m dv / dt

        dv = (β – α t) dt

     

We integrate

        v = β t - ½ α t²

We evaluate between the lower limits v = v₀ for t = 0 and the upper limit v = v for t = t

       v-v₀ = β t - ½ α t²

the farthest point of the body is when v = v₀ = 0

  0 = β t - ½ α t²

  t = 2 β / α

  t = 2 4/6

  t = 4/3 s

Let's find the distance at this time

   v = dx / dt

   dx / dt = v₀ + β t - ½ α t2

   dx = (v₀ + β t - ½ α t2) dt

We integrate

   x = v₀ t + ½ β t - ½ 1/3 α t³

   x = v₀ 4/3 + ½ 4 (4/3)² - 1/6 6 (4/3)³

The body comes out of rest

    x = 3.5556 - 2.37

    x = 1,185 m

The value of force is

    F = β - α t

    F = 4 - 6 4/3

   F = - 4 N

You might be interested in
You push very hard on a heavy desk, trying to move it. You do work on the desk:
frozen [14]

Answer:

(C) Only if it starts moving

Explanation:

We know that work done is given by

W=F.d=Fdcos\Theta

So there are two case in which work done is zero

First case is that when force and displacement are perpendicular to each other

And other case is that when there is no displacement

So for work to be done there must have displacement, if there is no displacement then there is no work done

So option (c) will be the correct option

3 0
3 years ago
A cheetah starts from rest and accelerated at 8.7 m/s^2 for 3s. How far did the cheetah go in that time
nika2105 [10]

Answer:

cheetah goes 52.2 m in that time.

Explanation:

4 0
3 years ago
Which of the following best describes the term thermal energy? Choose one: A. The energy of an object in motion due to its mass
o-na [289]

Answer:

The correct option is (d).

Explanation:

  • The energy a particle has because of its charge and its position relative to another particle is called thermal energy.
  • It is the energy that comes from heat. This is generated by the movement of the particles in an object.
  • Thermal energy is the energy an object or system has due to the movement of particles within.

Hence, the correct option is (d).

8 0
3 years ago
If you have a piece of brass and a piece of aluminurn that have the same volume, which will have a larger mass?
vfiekz [6]

Answer:

the aluminum would have the most mass

6 0
3 years ago
Andrew is pushing this block to the right across on the floor. Which force in the free body diagram is pointing in the wrong dir
soldier1979 [14.2K]

Answer:

the normal force

Explanation:

The free-body diagram represents all the forces acting on an object. In this example, there are four forces acting on the box: an applied force, the friction (which always act opposite to the applied force), the weight of the box (which is always downward), and the normal force.

The normal force is the reaction force exerted by the surface on which the box is moving on the box, and this reaction force is always opposite to the force exerted by the box on the surface. Since the latter is downward, it means that the normal force must be upward, so in the diagram it is wrong.

8 0
3 years ago
Read 2 more answers
Other questions:
  • How does mass affect the gravitational pull of the Sun, Earth, and the Moon?
    9·2 answers
  • A child is sliding down a slide at the playgound. is mechanicalenergy conserved
    12·1 answer
  • What information can be deduced by analyzing the graph?
    5·2 answers
  • What is the wavelength of an earthquake wave if it has a speed of 7 km/s and a frequency of 3 Hz?
    11·1 answer
  • A yellow ball with a mass of 2 kg is rolling across the floor at 3 mis. A red ball with a mass of 3 kg is rolling across th
    5·1 answer
  • A circular test track for cars has a circumference of 3.5 kmkm . A car travels around the track from the southernmost point to t
    11·1 answer
  • “Why can I sometimes see the moon during the day?“Why can I sometimes see the moon during the day?
    10·1 answer
  • 1 five disadvantages of frictions<br>​
    11·1 answer
  • A sprinter starts from rest and reaches a speed of 15 m/s in 4.25 s. Find his acceleration
    10·1 answer
  • Which arrow represents the substance’s change of state?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!