Answer:
The radius is
Explanation:
From the question we are told that
The speed at which the race car moves is 
The centripetal acceleration is 
Generally the centripetal acceleration is mathematically represented as

=> 
=>
Answer:
The answer is (d) is totally reflected
Explanation:
Using the total internal reflection concept.
This concept state that:
"If the angle of incidence is greater than the critical angle then the light will not refract but it will reflect back totally"
Using the above statement, as incident angle is 42 degree and critical angle is 41 degree it means incident angle is greater than the critical angle. Therefore, light will not refract but it will totally reflected.
The answer is
h: sB and Sb
hd : sb
hr : SB
Answer:
When you have a cloudy night, the clouds prevent heat from escaping through the atmosphere and into space.
The clouds act like a blanket and trap the heat it, and that is why every time you have a cloudy night, it is always warmer than a clear night.