Answer:
A
Explanation:
Speed of light is 299 792 458 m / s. So option A is answer.
Answer:
Option (b) is correct.
Explanation:
The motion under the influence of gravity is called projectile motion.
The acceleration due to gravity is constant through out the motion and it is always acting downwards.
When an athlete jumps and follow the projectile path, it always have the same horizontal velocity as there is no acceleration in the horizontal direction.
Also he has the vertical acceleration constant which is equal to the acceleration due to gravity and acts towards the center of earth.
Option (b) is correct.
To find out the kinetic friction, using the coefficient friction formula.
What is kinetic friction?
A force that acts between moving surfaces is called "kinetic friction." A force acting in opposition to the direction of a moving body on the surface is felt. The two materials' kinetic friction coefficients will determine how much force is applied.
What is coefficient friction?
A measure of the degree of friction between two surfaces is the coefficient of friction. A coefficient of friction is determined by calculating the resistance to motion at the intersection of two surfaces made of the same or different materials.
UK
U-coefficient of friction
K-Kinetic friction
Using UK
450+370-f=m*o
f=820=UK*260*9.8
UK=2.548
820/2.548
UK= 321.8210361
Therefore the coefficient of kinetic friction is 321.8210361
Learn more about Kinetic friction from the given link.
brainly.com/question/14111192
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the answer is b. it's commercially reprocessed