The severity of the seasons on Earth is given not by the distance Earth-Sun but by the tilt of the Earth axis. This happens because that the sun rays are oblique in winter and perpendicular in summer (thus the same quantity of sun rays heats a bigger surface in winter - oblique rays).
The present tild of the Earth axis is 23.5 degrees (from the vertical). If the axis were tilt at 157 degree this would be equivalent to 180-157 =23 degree. Thus the severity of the seasons would be approximately the same but the seasons would be reversed (for example instead of winter we would have summer, instead of summer we would have winter).
Answer:
option C
Explanation:
Given,
Refractive index of medium 1 = n₁
Refractive index of medium 2 = n₂
For total internal reflection to take place light should move from denser medium to the rarer medium.
Here Total internal reflection take place at the boundary of medium 1 and medium 2 so, the refractive index of medium 1 is more than medium 2
n₁ > n₂
The correct answer is option C
Answer:
Option A
Explanation:
Mechanical waves requires some medium to travel through. They travel faster in the dense medium as compared to a free medium.
The speed of a mechanical wave is fastest in the solid medium and the slowest in the gaseous medium. Hence, as the wave traverses from gaseous medium to the solid medium, its speed increases.
Thus, option A is correct
Explanation:
A charge alters the space around it. This alteration of space is called the electric field. It is also defined as the electric force acting on a charged particle per unit test charge. It is given by :

Where
F is the electric force, 
The direction of electric field is in the direction of electric force. For a positive charge, the direction of electric field lines are outwards and for a negative charge, the direction of field lines are inwards.
Hence, the correct option is (c) "electric field".
Answer:
Centripetal acceleration = 83.77m/s²
Explanation:
<u>Given the following data;</u>
Radius, r = 0.13m
Velocity, v = 3.3m/s
To find centripetal acceleration;
Centripetal acceleration is given by the formula;
Substituting into the equation, we have;
<em>Centripetal acceleration = 83.77m/s²</em>
<em>Therefore, the centripetal acceleration of the edge of the disc is 83.77 m/s². </em>