Answer:
D: Scientists have not been successful in disproving the atomic theory.
Explanation:
This theory has had great implications in the understanding of nature at the microscopic level, from the first atomic model to the quantum model of the atom. All modern physics, chemistry and biochemistry are based on the theory that matter is composed of atoms of different elements. It has not been possible to disprove this theory or replace it with a better one.
Answer:
○ 0 
Explanation:
Even if the athelete runs four laps of a 400 m track, its displacement will be 0 because the displacement is the shortest distance from its to final position. And, here the final and initial position is same since he comes to its initial position after covering certain distance. So, displacement is 0.
<u>Answer:</u>
1) Distance traveled by bird = 403 meter
2)Average speed = 1.66 km /hour
3) Zcceleration = 2 
<u>Explanation:</u>
1) Distance traveled = Speed * Time taken = 31 * 13 = 403 meter.
2) Average speed = Total distance covered / Time taken for that distance to cover.
Total distance covered = 2+0.5+2.5 = 5 km
Time taken = 3 hours
Average speed = 5/3 = 1.66 km /hour
3) Acceleration is defined as the rate of change of velocity, so acceleration a = change in velocity/time.
Change in velocity = 14 - 6 = 8 m/s
Time = 4 seconds
So acceleration = 8 / 4 = 2 
Answer:
Option 3: -48 cm
Explanation:
We are given:
refractive index; n = 1.5
radius of curvature; r2 = 24 cm
Formula for the focal length is given as;
1/f = (n - 1) × [(1/r1) - (1/r2)]
As r1 tends to infinity, 1/r1 = 0
Thus,we now have;
1/f = (n - 1) × (-1/r2)
Plugging in the relevant values;
1/f = (1.5 - 1) × (-1/24)
1/f = -0.02083333333
f = -1/0.02083333333
f = -48 cm
Answer:
Temperature at which the resistance is twice the resistance at
is 
Solution:
As per the question:
Temperature coefficient, 
Reference temperature, 
Resistance, 
Now, using the formula:





- Yes, this temperature holds for all all the conductors of copper, irrespective of the size and shape of the conductor.