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
sweet [91]
3 years ago
14

Consider two wires made of copper. They have the same diameter but one of them has three times the length of the other. Choose t

he correct statement:
a. Both wires have the same resistivity
b. The long wire has one third of the resistivity of the short wire
c. None of the other answers is correct
d. The long wire has three times the resistivity of the short wire
Physics
1 answer:
boyakko [2]3 years ago
6 0

Answer:

a. Both wires have the same resistivity

Explanation:

For the resistance of a wire , following formula holds good .

R = ρ l / S , R is resistance , l is length , S is cross sectional area and ρ is resistivity of the material that the wire is made of. Resistance is dependent on length and cross sectional area but resistivity does not depend upon length or cross sectional area . It only depends upon the type of material.

If we replace  copper wire with aluminium wire , then resistivity will change .

Hence , since the wire remains made of copper , resistivity will not change.

You might be interested in
What type of energy is the sum of an object’s potential and kinetic energy?
nikklg [1K]

Answer: its mechanical energy

Explanation:

8 0
3 years ago
The normal force acting on an object and the force of static friction do zero work on the object. However the reason that the wo
spin [16.1K]

Answer:

<em>The normal force is perpendicular to the displacement</em>

<em>The static friction force produces no displacement</em>

Explanation:

Work Done By Special Forces

The work is a physical magnitude that measures the dot product of the force applied to an object by the displacement it produces in it.

W=\vec F\ \vec r

It can be written in its scalar version as

W=F.d.cos\theta

Being F and d the magnitudes of the force and displacement, and \theta the angle between them

If the angle is zero, the work is at maximum, it the angle is 90°, the work is zero. If the angle is between 90° and 180°, the work is negative.

The normal force acts in the vertical direction when the object is being pushed horizontally. It means the angle between the force and the displacement is 90°, thus the work is

W=N.d.cos90^o=0

The work is zero because the force and the displacement are perpendicular

The static friction force exists only when the object is being applied a force of a magnitude not large enough to produce movement, i.e. the object is at rest. If the object is moved, the friction force is still present, but it's called dynamic friction force, usually smaller than the static.

Since in this case, there is no displacement, d=0, and the work is

W=F_r(0)cos180^o=0

3 0
3 years ago
The formula v = √2.5r models the maximum safe speed, v, in miles per hour, at which a car can travel on a curved road with radiu
mel-nik [20]

Answer:

The maximum safe speed of the car is 30.82 m/s.

Explanation:

It is given that,

The formula that models the maximum safe speed, v, in miles per hour, at which a car can travel on a curved road with radius of curvature r r, is in feet is given by :

v=\sqrt{2.5\ r}.........(1)

A highway crew measures the radius of curvature at an exit ramp on a highway as 380 feet, r = 380 feet

Put the value of r in equation (1) as :

v=\sqrt{2.5\ \times 380}

v = 30.82 m/s

So, the maximum safe speed of the car is 30.82 m/s. Hence, this is the required solution.

4 0
3 years ago
Provide a general expression to clearly describe how to use yourknowlegde of an atom's composition to determine the sign and mag
nikdorinn [45]
The net charge on an atom is equal to the overall difference between the number of protons in the nucleus versus the number of electrons around the nucleus, where a negative sign represents less protons and a positive sign represents more protons (than electrons).
7 0
3 years ago
Which best explains why a black T-shirt gets warmer in the Sun than a white T-shirt?
maxonik [38]

Answer:

Black t shirt

Explanation:

It absorbs more heat than the white shirt

6 0
2 years ago
Read 2 more answers
Other questions:
  • Two technicians are discussing disc brake rotor service. Technician A says that the inner races (bearing cups) should be removed
    15·1 answer
  • PLEASE HELP ASAP!!!!!! <br> What should each experiment only have one of? <br> variable or constant
    12·2 answers
  • Plz help me I’m a desperate little boy
    8·1 answer
  • An example of an insulator is
    9·1 answer
  • Explain what is the difference of physical and chemical weathering
    10·1 answer
  • A satellite in orbit around the Earth has a speed of 8 km/s at a given point of its orbit. If the period is 2 h, what is the alt
    14·1 answer
  • Write the adverbs use in sentences no.1-5 ty​
    13·1 answer
  • Define critical angle<br>​
    12·1 answer
  • What speed must an electron have if its momentum is to be the same as that of an x-ray photon with a wavelength of 0. 85 nm?
    6·1 answer
  • Bonds: Including Carbon Compounds Quick Check
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!