Answer:
The reflection and rectilinear propagation of light helps in the formation of shadows and also tells light doesn't penetrate opaque materials.
Answer:
the answer is B: earth takes to rotate once on its axis
Answer:
this statement describes meteor's velocity,
because velocity is a vector quantity which has both magnitude as well as a specific direction and here the meteor's direction is specified in the statement hence we conclude that this statement describes meteor's velocity as well as speed too.
Answer:
Work done will be 2.205 j
Explanation:
We have given that the spring is compressed b 37.5 cm
So d = 0.375 m
Mass of the block m = 600 gram = 0.6 kg
Acceleration due to gravity 
Gravitational force on the block 
Now we know that work done is give by 
Answer:
r = √(k q₁ q₂ / F)
Explanation:
F = k q₁ q₂ / r²
Multiply both sides by r²:
F r² = k q₁ q₂
Divide both sides by F:
r² = k q₁ q₂ / F
Take the square root of both sides:
r = √(k q₁ q₂ / F)