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.
Answer:
Difference between heat and temperature in tabular form
Heat vs Temperature
1.Heat is a form of energy that can transfer from a hot body to a cold body. and Temperature is the degree of hotness and coldness of a body.
2.Heat is the total kinetic energy and potential energy obtained by molecules in an object. and Temperature is the average K.E of molecules in a substance.
3.Heat flows from hot body to cold body. It rises when heated and falls down when an object is cooled down and It has a working ability. It does not have the working ability
.
4.Its SI unit is “Joule” and Its SI unit is “Kelvin”.
5.It is measured by the calorimeter and It is measured by the thermometer
.
6.It is represented by “Q”. and It is represented by “T”.
Explanation:
A calorimeter is an object used for calorimetry, or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity. ... A simple calorimeter just consists of a thermometer attached to a metal container full of water suspended above a combustion chamber.
Answer:
Time taken = 10400 s
Explanation:
Given:
Initial speed of the train, 
Final speed of the train, 
Displacement of the train, 
Using Newton's equation of motion,

Now, using Newton's equation of motion for displacement,

Now, plug in the value of
in the above equation. This gives,

Now, plug in 234000 m for
, 25 m/s for
and 20 m/s for
. Solve for
.

Therefore, the time taken by the train is 10400 s.
Answer:
Mass of the oil drop, 
Explanation:
Potential difference between the plates, V = 400 V
Separation between plates, d = 1.3 cm = 0.013 m
If the charge carried by the oil drop is that of six electrons, we need to find the mass of the oil drop. It can be calculated by equation electric force and the gravitational force as :


, e is the charge on electron
E is the electric field, 


So, the mass of the oil drop is
. Hence, this is the required solution.
Answer:
#1 ( Balanced ) ( Rest)
#2 ( Unbalanced) ( Accelerating)
Explanation: