Answer:
v = c / n (n = 1 for air)
v = c / 1.33 = 3 * 10E8 m/s / 1.33 = 2.25 * 10E8 m/s
Answer:
3.64 m
Explanation:
m = Mass of object = 70 kg
Kinetic energy of the object = 2500 J
g = Acceleration due to gravity = 
h = Height from which the object is dropped
Kinetic energy is given by

From conservation of energy we get kinetic energy equal to potential energy.

The object was released from a height of 3.64 m.
The speed does the block move after it is hit by the bullet that remains stuck inside the block will be 23.7 m/sec and it takes 12.07 seconds to stop.
<h3>What is the law of conservation of momentum?</h3>
According to the law of conservation of momentum, the momentum of the body before the collision is always equal to the momentum of the body after the collision.
Apply the law of conservation of momentum principle;
m₁v₁+m₂v₂cosΘ =(m₁+m₂)V
3 kg × 12 m/s + 0,1 kg × 400 m/s cos 20° = (3+0.1)V
36 + 40 cos 20° = 3.1 V
V=23.7 m/sec
The time it takes to stop when the friction coefficient between the block and the surface is 0.2 is found as;
V = u +at
V = 0+ μgt
23..7=0.2× 9.81 ×t
t=12.07 sec
Hence, it takes 12.07 seconds to stop.
To learn more about the law of conservation of momentum refer;
brainly.com/question/1113396
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Answer:
second
Explanation:
the first let's everything appear red, the send would produce black(-ish) words on paper that's appealing blue