Solution: The correct order is: C, A, B
The statement of the problem:
How can we prove Earth is round and calculate its circumference?
Hypotheis:
If the sun casts shadows at different angles at the same time of day in different places, we can determine how much Earth curves.
If the Earth was flat, the angle measured at different places at the same time of the day would be same.
Observation:
In Syene, the sun's rays are vertical at noon. At the same time in Alexandria, the rays are 7.2 degrees from the vertical.
Answer:
0.83 m or 5.57 m
Explanation:
Destructive interference will occur when the distances from the speakers differ by 1/2 wavelength.
The length of 1 cycle of 72.4 Hz is ...
λ = v/f = (343 m/s)/(72.4 Hz) ≈ 4.738 m
So, the distance of the listener from speaker B is ...
3.2 m ± (4.738 m)/2 = {0.83 m, 5.57 m} . . . either of these distances
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The location could be at additional multiples of 4.738 m, but we think not. The sound intensity drops off with the square of the distance from the speaker, so identical sound waves from the speakers will sound quite different at different distances from the speakers. For best interference, the distances need to be as close to the same as possible. That will be at 3.2 m and 5.57 m.
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<em>Comment on the speed of sound</em>
We don't know what speed you are to use for the speed of sound. We have used 343 m/s. Some sources use 340 m/s, which will give a result different by 2 or 3 cm.
Answer:
The magnitude of the torque on the loop due to the magnetic field is
.
Explanation:
Given that,
Diameter = 10 cm
Current = 0.20 A
Magnetic field = 0.30 T
Unit vector
We need to calculate the torque on the loop
Using formula of torque

Where, N = number of turns
A = area
I = current
B = magnetic field
Put the value into the formula


Hence, The magnitude of the torque on the loop due to the magnetic field is
.
Answer:
Explanation:
Given
mas of block 
speed of block 
spring constant 
As the mass collides with the spring its kinetic energy is converted to the Elastic Potential energy of the spring




Explanation:
Force Description
1.
It is also known as the weight of an object. It is the force that is exerted on an object due to its mass
2.
It is force which is exerted by a push or a pull on an object. It is also known as applied force.
3.
It is known as resistive force. It opposes the motion of an object.
4.
It is the force which is at a right angle to the surface or perpendicular to the surface.