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
Dmitry_Shevchenko [17]
4 years ago
3

In a contest, two tractors pull two identical blocks of stone thesame distance over identical surfaces. However, block A is movi

ng twice as fast as block B when it crosses the finish line. Which statement is correct?a) Block A has twiceas much kinetic energy as block B.b) Block B has losttwice as much kinetic energy to friction as block A.c) Block B has losttwice as much kinetic energy as block A.d) Both blocks havehad equal losses of energy to friction.e) No energy is lostto friction because the ground has no displacement.
Physics
1 answer:
Arturiano [62]4 years ago
5 0

Answer:

d) Both blocks have had equal losses of energy to friction

Explanation:

As it is mentioned in the question that two tractors pull two same stone blocks having the identical distance over the same surfaces

Moreover, the block A is twice as fast than block B at the time of crossing the finish line

So based on the above information,  it contains the losses of identical friction

And we also know that

Friction energy loss is

= \mu \times m \times g \times D

It would be the same for both the blocks

hence, the option d is correct

You might be interested in
A 540 g model rocket is on a cart that is rolling to the right at a speed of 2.5 m/s. The rocket engine, when it is fired, exert
frez [133]

Answer:

horizontal distance left of the loop should you launch is 7.1m

Explanation:

See attached file

4 0
3 years ago
Can someone explain this to me? 20 POINTS!
Anarel [89]

Answer:What is the first law of thermodynamics and how does it relate to energy use? The first law of thermodynamics states that energy is conserved in chemical processes. ... This amount of energy that must be lost to the surroundings for the process to occur is nature's heat tax, an unavoidable cut of every energy transaction.

Explanation:

3 0
3 years ago
A rock is tossed straight up from the ground with a speed of 21 m/s . When it returns, it falls into a hole 10 m deep.a.) What i
Arte-miy333 [17]

(a) 25.2 m/s

Let's take the initial vertical position of the rock as "zero" (reference height).

According to the law of conservation of energy, the speed of the rock as it reaches again the position "zero" after being thrown upwards is equal to the initial speed of the rock, 21 m/s (in fact, if there is no air resistance, no energy can be lost during the motion; and since the kinetic energy depends only on the speed of the rock:

K=\frac{1}{2}mv^2

and the gravitational potential energy of the rock has not changed, since the rock has returned into its initial position, it means that the speed of the rock should be the same)

This means that we can only analyze the final part of the motion, the one in which the rock falls into the 10 m hole. Since it is a free fall motion, we can find the final speed by using

v^2 = u^2 + 2gd

where

u = 21 m/s is the initial speed of the rock as it enters the hole

g = 9.8 m/s^2 is the acceleration due to gravity

d = 10 m is the depth of the hole

Substituting,

v=\sqrt{u^2 +2gd}=\sqrt{(21 m/s)^2+2(9.8 m/s^2)(10 m)}=25.2 m/s

(b) 4.72 s

The vertical position of the rock at time t is given by

y(t) = v_y t - \frac{1}{2}gt^2

where

v_y = 21 m/s is the initial vertical velocity

Substituting y(t)=-10 m, we can then solve the equation for t to find the time at which the rock reaches the bottom of the hole:

-10 = 21 t - \frac{1}{2}(9.8)t^2\\10+21 t -4.9t^2 = 0

which has two solutions:

t = -0.43 s --> negative, so we discard it

t = 4.72 s --> this is our solution

7 0
4 years ago
A 12-V battery is connected to an air-filled capacitor that consists of two parallel plates,
zloy xaker [14]

Answer:

E = 4000 V / m

U = 1.92*10^-18 J

C' = 4.71 pF

1.2 times greater with di-electric

Explanation:

Given:-

- The potential difference between plates, V = 12 V

- The area of each plate, A = 7.6 cm^2

- The separation between plates, d = 0.3 cm

- The charge of the proton. q = 1.6*10^-19 C

- The initial velocity of proton, vi = 0 m/s

Solution:-

- The electric field ( E ) between the parallel plates of the air-filled capacitor is determined from the applied potential difference by the battery on the two ends of the plates.

- The separation ( d ) between the two plates allows the charge to be stored and the Electric field between two charged plates would be:

                          E = V / d

                          E = 12 / 0.003

                          E = 4,000 V/m ... Answer

- The amount of electrostatic potential energy stored between the two plates is ( U ) defined by:

                         U = q*E*d

                         U = (1.6 x10^-19)*(4000)*(0.003)

                         U = 1.92*10^-18 J  ... Answer

- The electrostatic energy stored between plates is ( U ) when the proton moves from the positively charges plate to negative charged plate the energy is stored within the proton.

- A slab of di-electric material ( Teflon ) is placed between the two plates with thickness equal to the separation ( d ) and Area similar to the area of the plate ( A ).

- The capacitance of the charged plates would be ( C ):

                        C = k*ε*A / d

Where,

            k: the di-electric constant of material = 2.1

            ε: permittivity of free space = 8.85 × 10^-12

- The new capacitance ( C' ) is:

                      C' = 2.1*(8.85 × 10^-12) *( 7.6 / 100^2 ) / 0.003

                      C' = 4.71 pF

- The new total energy stored in the capacitor is defined as follows:

                     U' = 0.5*C'*V^2

                     U' = 0.5*(4.71*10^-12)*(12)^2

                     U' = 3.391 * 10^-10 J

- The increase in potential energy stored is by the amount of increase in capacitance due to di-electric material ( Teflon ). The di-electric constant "k" causes an increase in the potential energy stored before and after the insertion.

- Hence, the new potential energy ( U' ) is " k = 2.1 " times the potential energy stored in a capacitor without the di-electric.

                     

4 0
3 years ago
Give an example of a system whose mass is not constant.
Sloan [31]
A spinning top is the answer
8 0
3 years ago
Other questions:
  • The tonga trench in the pacific ocean is 36,000 feet deep. assuming that sea water has an average density of 1.04 g/cm3, calcula
    5·1 answer
  • Give an example of forces adding together
    15·1 answer
  • The idea of the atom was first proposed by____?<br> Democritus<br> John dalton <br> Neils bohr
    10·2 answers
  • What is it when When humans control breeding of other organisms to favor certain traits
    8·1 answer
  • What force is required to cause a 5 kg bowling ball to accelerate at 4 m/s2​
    5·1 answer
  • Is 51/17 a rational number
    8·2 answers
  • The transformer supplying power to an artist's light sculpture provides 9600-V AC when supplied by 120-V AC. If there are 100 tu
    11·1 answer
  • If the earth shrank until its radius were only one-quarter its present size without changing its mass what would a 20 n object w
    11·1 answer
  • How does size of an object affect its gravity
    7·1 answer
  • Depth of a pond seems shallower than real depth,why?​
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!