Final answer:
Using the kinematic equation for distance with an initial velocity of 0, we can calculate the time it takes a hockey player to skate 30 m with an acceleration of 2.1 m/s² to be approximately 5.3 seconds, corresponding to option B.
Step-by-step explanation:
To solve this problem, we can use the kinematic equation d = vit + (1/2)at², where 'd' is the distance the hockey player skates, 'vi' is the initial velocity, 'a' is the acceleration, and 't' is the time taken. Since the hockey player starts from rest, 'vi' is 0. Substituting the given values into the equation, we get 30 m = 0 m/s * t + (1/2)(2.1 m/s²) * t².
Simplifying the equation gives us 30 m = 1.05 m/s² * t². To find 't', we can rearrange the equation to t² = 30 m / 1.05 m/s², which simplifies to t² = approximately 28.57 s². Taking the square root of both sides, we find that t is approximately √28.57 s² or about 5.35 s.
Therefore, the time it takes for the hockey player to skate 30 m is approximately 5.3 seconds, which corresponds to option B.