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
Alborosie
3 years ago
6

A block of mass m1 = 3.5 kg moves with velocity v1 = 6.3 m/s on a frictionless surface. it collides with block of mass m2 = 1.7

kg which is initially stationary. the blocks stick together and encounter a rough surface. the blocks eventually come to a stop after traveling a distance d = 1.85 m . what is the coefficient of kinetic friction on the rough surface? μk =
Physics
1 answer:
maxonik [38]3 years ago
3 0
First, let's find the speed v_i of the two blocks m1 and m2 sticked together after the collision.
We can use the conservation of momentum to solve this part. Initially, block 2 is stationary, so only block 1 has momentum different from zero, and it is:
p_i = m_1 v_1
After the collision, the two blocks stick together and so now they have mass m_1 +m_2 and they are moving with speed v_i:
p_f = (m_1 + m_2)v_i
For conservation of momentum
p_i=p_f
So we can write
m_1 v_1 = (m_1 +m_2)v_i
From which we find
v_i =  \frac{m_1 v_1}{m_1+m_2}= \frac{(3.5 kg)(6.3 m/s)}{3.5 kg+1.7 kg}=4.2 m/s

The two blocks enter the rough path with this velocity, then they are decelerated because of the frictional force \mu (m_1+m_2)g. The work done by the frictional force to stop the two blocks is
\mu (m_1+m_2)g  d
where d is the distance covered by the two blocks before stopping.
The initial kinetic energy of the two blocks together, just before entering the rough path, is
\frac{1}{2} (m_1+m_2)v_i^2
When the two blocks stop, all this kinetic energy is lost, because their velocity becomes zero; for the work-energy theorem, the loss in kinetic energy must be equal to the work done by the frictional force:
\frac{1}{2} (m_1+m_2)v_i^2 =\mu (m_1+m_2)g  d
From which we can find the value of the coefficient of kinetic friction:
\mu =  \frac{v_i^2}{2gd}= \frac{(4.2 m/s)^2}{2(9.81 m/s^2)(1.85 m)}=0.49
You might be interested in
At exactly 3:14PM, the velocity of a dog running in a park points toward a group of flowers. Which of the following best describ
dmitriy555 [2]

Answer:

Options A, B, and C are all possible.

Explanation:

We know that the instantaneous velocity of the dog at 3:14PM is possitive to toward the flowers. But what about the acceleration to toward the flowers?

If the dog is decreasing speed at 3:14PM, it means that acceleration is negative toward the flowers, hence (since F=ma) the net force points away from the flowers.

If the dog is increasing speed at 3:14PM, it means that acceleration is positive toward the flowers, hence (since F=ma) the net force points toward the flowers.

If the dog is not increasing nor decreasing speed at 3:14PM, it means that acceleration is 0, hence (since F=ma) the net force is null and it does not point neighter to toward the flowers  nor away from the flowers. This happens when the forces acting on the dog are equal to both sides.

4 0
3 years ago
The electric field between two parallel plates has a magnitude of 875 n/
Marizza181 [45]
The answer:
1.8 x 10^0 V
7 0
3 years ago
A solution is a homogeneous mixture of one or more solutes dissolved in a solvent. A specific volume of solvent is only able to
Luba_88 [7]
<h3><u>Answer;</u></h3>

C. Supersaturated

<h3><u>Explanation</u>;</h3>
  • Solutions are homogeneous mixtures that are created by mixing a solute and a solvent. Solute is the substance present in smaller amounts that dissolves in a solvent such as water which is the substance present in larger amount.
  • A solution, can be<u> unsaturated, saturated or supersaturated. An unsaturated solution</u> is a solution that contains less solute that can be dissolved, it doesn't contain the maximum amount of solute.
  • <u>A saturated solution</u> is a solution containing the maximum amount of solute that can be dissolved at a given temperature. Any additional solute will remain undissolved in the container.
  • <u>A supersaturated solution</u> is a solution created when a solution is carefully cooled because it contains more solute than the solubility allows.
7 0
3 years ago
Read 2 more answers
A toy rocket is fired vertically into the air from the ground at an initial velocity of 80 feet per second. Find the time it wil
miskamm [114]

Answer: 16.3 seconds

Explanation: Given that the

Initial velocity U = 80 ft/s

Let's first calculate the maximum height reached by using third equation of motion.

V^2 = U^2 - 2gH

Where V = final velocity and H = maximum height.

Since the toy is moving against the gravity, g will be negative.

At maximum height, V = 0

0 = 80^2 - 2 × 9.81 × H

6400 = 19.62H

H = 6400/19.62

H = 326.2

Let's us second equation of motion to find time.

H = Ut - 1/2gt^2

Let assume that the ball is dropped from the maximum height. Then,

U = 0. The equation will be reduced to

H = 1/2gt^2

326.2 = 1/2 × 9.81 × t^2

326.2 = 4.905t^2

t^2 = 326.2/4.905

t = sqrt( 66.5 )

t = 8.15 seconds

The time it will take for the rocket to return to ground level will be 2t.

That is, 2 × 8.15 = 16.3 seconds

8 0
3 years ago
This phenomenon is known as the bends. If a scuba diver rises quickly from a depth of 25.0 m in Lake Michigan (which is fresh wa
Sveta_85 [38]

Explanation:

Attachments of the solution are below.

6 0
3 years ago
Other questions:
  • Which equation could be rearranged to calculate the frequency of a wave?
    6·1 answer
  • Why do we have day light savings time? Please help me I need the mechanics.
    8·1 answer
  • Evolution refers to which of the following? A. having traits that help a species survive B. the gradual change of a species over
    8·1 answer
  • Consider the system shown in fig. 6-26. the rope and pulley have negligible mass, and the pulley is frictionless. the coefficien
    8·1 answer
  • Ammonia is a weak base because produce ____ ion in solution?
    6·2 answers
  • Three solid, uniform, cylindrical flywheels, each of mass 65.0 kg and radius 1.47 m, rotate independently around a common axis t
    12·1 answer
  • Suppose that the voltage across the resistor is held constant at 40 volts. If the resistance is steadily decreasing at a rate of
    14·1 answer
  • What is the difference in force of a car and a tractor
    10·1 answer
  • Calcula qué tan lejos está Saturno del Sol, sabiendo que la luz solar necesita una hora y veinte segundos para llegar a Saturno.
    9·1 answer
  • If a mass of 1 kg is accelerated to 1 m/s2 by a force of 1 N, then
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!