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
stellarik [79]
3 years ago
14

An object is attached to a vertical spring and bobs up and down between points A and B. Where is the object located when its kin

etic energy is a minimum?
a. at either A or B
b. midway between A and B
c. one-third of the way between A and B
d. one-fourth of the way between A and B
Physics
1 answer:
gtnhenbr [62]3 years ago
4 0

Answer:

a. at either A or B

Explanation:

Kinetic energy may be defined as the energy of the system or an object which is due to its velocity of the object it possess.

In the context, an object having mass  is attached to spring which is vertical and the object moves up and down due to spring effect between points A and B. Now these points A and B are the extreme points after which the object bounces back.

At point A and B, the velocity of the object becomes zero and hence the kinetic energy of a body varies directly proportional to its velocity.

                  i.e. Kinetic energy $= \frac{1}{2} \text{mass} \times (\text{ velocity})^2$  

You might be interested in
A large crate with mass m rests on a horizontal floor. The static and kinetic coefficients of friction between the crate and the
rjkz [21]

Answer:

a) F=\frac{\mu_{k}mg}{cos \theta-\mu_{k}sin \theta}

b) \mu_{s}=\frac{Fcos \theta}{Fsin \theta +mg}

Explanation:

In order to solve this problem we must first do a drawing of the situation and a free body diagram. (Check attached picture).

After a close look at the diagram and the problem we can see that the crate will have a constant velocity. This means there will be no acceleration to the crate so the sum of the forces must be equal to zero according to Newton's third law. So we can build a sum of forces in both x and y-direction. Let's start with the analysis of the forces in the y-direction:

\Sigma F_{y}=0

We can see there are three forces acting in the y-direction, the weight of the crate, the normal force and the force in the y-direction, so our sum of forces is:

-F_{y}-W+N=0

When solving for the normal force we get:

N=F_{y}+W

we know that

W=mg

and

F_{y}=Fsin \theta

so after substituting we get that

N=F sin θ +mg

We also know that the kinetic friction is defined to be:

f_{k}=\mu_{k}N

so we can find the kinetic friction by substituting for N, so we get:

f_{k}=\mu_{k}(F sin \theta +mg)

Now we can find the sum of forces in x:

\Sigma F_{x}=0

so after analyzing the diagram we can build our sum of forces to be:

-f+F_{x}=0

we know that:

F_{x}=Fcos \theta

so we can substitute the equations we already have in the sum of forces on x so we get:

-\mu_{k}(F sin \theta +mg)+Fcos \theta=0

so now we can solve for the force, we start by distributing \mu_{k} so we get:

-\mu_{k}F sin \theta -\mu_{k}mg)+Fcos \theta=0

we add \mu_{k}mg to both sides so we get:

-\mu_{k}F sin \theta +Fcos \theta=\mu_{k}mg

Nos we factor F so we get:

F(cos \theta-\mu_{k} sin \theta)=\mu_{k}mg

and now we divide both sides of the equation into (cos \theta-\mu_{k} sin \theta) so we get:

F=\frac{\mu_{k}mg}{cos \theta-\mu_{k}sin \theta}

which is our answer to part a.

Now, for part b, we will have the exact same free body diagram, with the difference that the friction coefficient we will use for this part will be the static friction coefficient, so by following the same procedure we followed on the previous problem we get the equations:

f_{s}=\mu_{s}(F sin \theta +mg)

and

F cos θ = f

when substituting one into the other we get:

F cos \theta=\mu_{s}(F sin \theta +mg)

which can be solved for the static friction coefficient so we get:

\mu_{s}=\frac{Fcos \theta}{Fsin \theta +mg}

which is the answer to part b.

3 0
3 years ago
Read 2 more answers
Sphere 1 with radius R_1 has positive charge q, Sphere 2 with radius 4.50 R_1 is far from sphere 1 and initially uncharged. The
tia_tia [17]

Answer:

Explanation:

capacitance of sphere 2 will be 4.5 times sphere 1

a ) when spheres are in contact they will have same potential finally . So

V_1 / V_2 = 1

b )

Charge will be distributed in the ratio of their capacity

charge on sphere1 = q  x 1 / ( 1 + 4.5 )

= q / 5.5

fraction = 1 / 5.5

c ) charge on sphere 2

= q x 4.5 / 5.5

fraction = 4.5 / 5.5

d ) surface charge density of sphere 1

= q /( 5.5 x A ) where A is surface area

surface charge density of sphere 2

= q x 4.5 /( 5.5 x 4.5² A ) where A is surface area

= q  /( 5.5 x 4.5 A )

q_1/q_2 = 4.5

6 0
3 years ago
What are the factors that affect the resistance of a wire?
777dan777 [17]

1) Length of the wire.

2) Thickness of the wire.

3) Temperature.

4) Type of metal.

Hope this helps!

-Payshence

6 0
3 years ago
If a roller coaster cart, with a mass of 100 kg, traveled this coaster, how much kinetic energy would it have at point 'E'?
zzz [600]

Answer:

Explanation:

Assuming no friction between the roller coaster car and the hill, and neglecting air resistance, the kinetic energy the roller coaster car would have at the bottom of the hill would be equal to its gravitational potential energy at the top of the hill, by conservation of energy.

8 0
3 years ago
What compound makes up carbohydrates?
Aliun [14]
The monomer of glucose makes up all carbohydrates
5 0
2 years ago
Other questions:
  • 3. A bus accelerates at 25 m/s/s. This allows the bus to speed up from 16 m/s to 172 m/s. How long
    7·1 answer
  • Identify the situations that have an unbalanced force. Check all that apply.
    7·2 answers
  • What makes the earth .
    11·1 answer
  • How do scientists look for black holes in the sky
    5·2 answers
  • A rocket sled with an initial mass of 3 metric tons, invluding 1 ton of fuel, rests on a level section of track. At t=0, the sol
    12·1 answer
  • A runner has a speed of 5m/s and a mass of 130 kg what is his kinetic energy?
    13·2 answers
  • Which statement does NOT explain the concept of the Doppler Effect? A. As an observer moves away from a stationary sound, the so
    6·1 answer
  • Brittney is on the starting line to run a track race. The distance around the track is 400m. She starts the race and runs 400m
    14·2 answers
  • Work done(as a measure of energy)=force x distance. Use this equation to show that the SI base units of energy are kg m^2 s^-2
    5·1 answer
  • television set changes electrical energy to sound and light energy. In this process, some energy is *
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!